JPH10160682A - Sample observation device and sample observation method using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display an infrared ray image and a visible light image for a sample simultaneously and easily fix the position of the infrared ray image in a sample by providing a traveling mechanism for moving an infrared ray camera and a visible light camera for observation at the same point of the sample to be observed. SOLUTION: A sample 10 is placed on a sample stand 5 and is moved by a sample stand traveling stage 6. It is moved by D in the direction of an arrow (h) by a one-axis stage 4 for observation by a visible light camera 2, thus matching to a light axis (n) of the visible light camera 2. Focusing is made by an upper/lower move mechanism and a site is determined while observing a monitor, thus performing observation. Then, an infrared ray camera 1 is moved by D in the direction of an arrow (g) by the one-axis stage 4, thus matching to a light axis (m) of the infrared ray camera 1. An infrared ray image is displayed on a monitor to observe a sample 10. The focal point of the infrared ray camera 1 is adjusted so that it is the same as that of the visible light camera 2 in advance so that the camera is moved by the one-axis stage 4 for switching an observation image and for displaying simultaneously.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sample observation apparatus for displaying an infrared image and a visible light image of a sample to be observed on the same screen, and an observation method using the apparatus.

[0002]

2. Description of the Related Art Conventionally, a microscope using an infrared camera with an infrared ray having a wavelength of 2 μm or more (hereinafter, referred to as an infrared microscope) is composed of an image observed by an infrared microscope (infrared image) and an image observed by visible light (visible light image). Is not provided at the same time, and when observing with infrared light, comparing the visible light image and the infrared image and identifying the same pattern etc. Was used to identify the location in the sample.

[0003]

However, an infrared image and a visible light image do not always show the same image. Further, an image that can be seen with infrared light but cannot be seen with visible light, and vice versa. Some images are invisible in the infrared
Depending on the sample to be observed, there may be no commonly observed image, and the position in the sample may not be easily identified.

Further, when the sample is a semiconductor substrate, a material having a low emissivity is generally used, and a portion which generates heat from a defective portion and a portion which does not generate heat when an integrated circuit formed on the semiconductor substrate conducts electricity for testing. When observing the temperature difference caused by the infrared microscope, a black body paint or the like may be applied to the surface of the semiconductor substrate, but when the black body paint is applied, the mirror surface becomes black and not only the pattern becomes invisible with visible light In addition, since the emissivity of infrared rays is uniform on the coated surface, a temperature difference may not appear, and it may be difficult to observe the pattern even with an infrared microscope.

The present invention has been made in view of the problems of the prior art,
A sample observation device that can simultaneously display an infrared image and a visible light image of a sample to be observed, and can easily identify the position of the infrared image in the sample, and that the sample is an object having a low infrared emissivity. Another object of the present invention is to provide an observation method capable of observing such a sample using this apparatus.

[0006]

In order to solve the above-mentioned problems, a sample observation device according to the present invention comprises an infrared camera 1 for detecting infrared light and outputting an image signal, and an infrared camera 1 for detecting visible light and generating an image signal. A visible light camera 2 to output, and a sample 1 to be observed by the infrared camera 1 and the visible light camera 2
A moving mechanism 4 for moving the infrared camera 1 and the visible light camera 2 so as to observe 0 at the same place;
Is provided. Thus, an infrared image and a visible light image can be obtained for the same portion of the sample to be observed, and these images can be displayed simultaneously.

[0007] Further, storage means 903 for storing image signals from the infrared camera and the visible light camera.
And an image processing means 901 for displaying an image based on these two stored image signals, whereby an infrared image and a visible light image can be displayed simultaneously.

[0008] Further, a storage means 903 for storing an image signal from either the infrared camera or the visible light camera, and an image based on the stored image signal and the image signal from the other of the infrared camera or the visible light camera. Image display means 901 for displaying an image based on an image signal
The observation image and the stored image signal can be displayed simultaneously while observing the sample by infrared light or visible light.

The moving mechanism includes a one-axis stage 4. The one-axis stage moves the infrared camera 1 and the visible light camera 2 while keeping the two cameras in parallel with each other. Switching can be easily performed, and both cameras can be positioned with high accuracy.

Further, the apparatus further comprises a sample moving mechanism 6 for moving the sample, wherein the storage means 903 stores the image signal of the visible light camera or the image signal of the infrared camera at a first observation position of the sample. When the observation position of the sample is changed from the first observation position to the second observation position by the sample moving mechanism 6, an image based on the stored image signal is displayed. Even if the observation position is changed to another position, a visible light image and an infrared image at the other position can be obtained. Therefore, even if the observation position of the sample is changed, it is possible to simultaneously display the infrared image and the visible light image by combining them.

According to another feature of the present invention, the above-described sample observation device is used to apply a substance that transmits visible light and has a high emissivity of infrared light to the sample and observes the sample. An observation method is provided. According to this, even when an object having a low emissivity of infrared rays such as silicon is used as a sample, observation with infrared rays becomes easy without affecting observation with visible light.

The infrared camera can be configured by including a two-dimensional sensor array and an infrared optical system, and the visible light camera can be configured by including a two-dimensional sensor array and a visible light optical system. Further, if these optical systems are microscope optical systems, observation is possible even if the sample is minute. Also,
The sample that can be observed by this apparatus may be any semiconductor substrate made of silicon or the like on which an integrated circuit is formed, or any substance that emits infrared rays such as microorganisms and living cells that emit infrared rays.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to FIGS. FIG. 1 is a diagram showing a sample observation microscope apparatus according to the present embodiment.
(A) is the front view, FIG.1 (b) is the side view.

The apparatus includes an infrared camera 1, a visible light camera 2, a member 3 to which the cameras 1 and 2 are attached, and a one-axis stage 4 for moving the member 3 relative to a sample table 5 described later. A sample stage 5 on which a sample 10 to be observed is placed, a sample moving stage 6 for moving the sample stage 5, a fixing member 7 for fixing the one-axis stage 4 to a gantry 8 to be described later, and this fixing A frame 8 on which the member 7 and the stage 6 are mounted and which are fixedly mounted is provided. A vertical movement mechanism (not shown) for vertically moving the sample stage 5 for focusing the cameras 1 and 2 is attached to the sample stage 5. The infrared camera 1 has a two-dimensional sensor array and an infrared microscope optical system (not shown), and the visible light camera 2 has a two-dimensional sensor array and a visible light microscope optical system (not shown).

The infrared camera 1 and the visible light camera 2 are fixed to the camera mounting member 3 so that their optical axes m and n are parallel to each other and the focus surfaces are at the same distance. The member 3 is fixed to a one-axis stage 4, and the stage 4 can move the infrared camera 1 and the visible light camera 2 while maintaining the state parallel to each other. That is, the cameras 1 and 2 can move in the directions of arrows h and g shown in FIG. 1A, and the amount of movement is the distance D between the optical axis m of the infrared camera 1 and the optical axis n of the visible light camera 2. It is. The two cameras 1 and 2 are positioned so as to observe the same part of the sample when observing the sample 10.

The infrared camera and the visible light camera are fixed, and the sample is moved by an XY stage on which the sample is mounted.
A method of obtaining a visible light image and an infrared image is also conceivable,
As in the present embodiment, it is easier to reciprocate the infrared camera and the visible light camera in only one direction using the one-axis stage to position the infrared camera and the visible light camera at a predetermined position, and the positioning accuracy is remarkably good. This solves the problem that occurs when the XY stage is used such that the sample is shifted during movement when the observation target is a living cell or the like.

Next, the operation of the present apparatus when observing a sample will be described. The sample 10 is placed on the sample stage 5, and the sample 10 is moved to an approximate position by the sample moving stage 6. For visible light observation by the visible light camera 2, the visible light camera 2 is moved by the distance D in the direction of the arrow h in FIG. At this time, the visible light observation position coincides with the optical axis n of the visible light camera 2. A visible light image from the visible light camera 2 is displayed on a monitor 901 (FIG. 2), focused by an up-down movement mechanism, and a sample movement stage 6 is finely moved to determine a site for observing the sample, and observation is performed.

Next, for infrared observation by the infrared camera 1, the infrared camera is moved by the uniaxial stage 4 in the direction of arrow g by the distance D, and is moved to the infrared observation position shown in FIG. At this time, the infrared observation position coincides with the optical axis m of the infrared camera 1. Infrared camera 1
Is displayed on a monitor, and the sample is observed. At this time, the focus of the infrared camera 1 is adjusted in advance to be the same as that of the visible light camera 2. In this manner, the infrared camera 1 and the visible light camera 2 are moved by the one-axis stage 4 to change the observation position, so that the observation image can be switched. Accordingly, an infrared image and a visible light image can be obtained for the same portion of the sample, and can be displayed simultaneously.

Next, the system configuration of the microscope sample observation device of the present embodiment will be described. FIG. 2 is a system configuration diagram of the present embodiment in which the personal computer 9 is provided in the microscope observation apparatus shown in FIG. Computer 9
Includes a frame memory 903 and an I / O board 902, and includes a monitor 901.

An infrared camera 1 and a visible light camera 2 are connected to the frame memory 903, and image signals from both cameras 1 and 2 are inputted. Then, the frame memory 90
Reference numeral 3 performs operations such as capturing an image signal from the camera, processing the image signal, and sending a signal to be displayed on the monitor 901. Images from the cameras 1 and 2 are displayed on the monitor 901 in real time via the frame memory 903. In addition, an infrared image and a visible light image are superimposed and displayed, or both images are separately displayed on the same screen. Thereby, both images can be displayed simultaneously. The I / O board 902 is connected with the one-axis stage 4 and the sample moving stage 6. The I / O board 902 controls a drive device (not shown) of each of the stages 4 and 6 according to an instruction from the computer 9, and The movements of 4 and 6 are controlled.

Next, an observation method using the present apparatus will be described by taking an example when observing a semiconductor substrate on which an integrated circuit is formed. Silicon (Si), which is a material of a semiconductor substrate,
It has a high infrared transmittance and is 3 to 5 μm or 8 to 1 which is a wavelength used by an infrared camera generally used for temperature measurement.
It transmits infrared light having a wavelength of 2 μm. Silicon also has an extremely low infrared emissivity (ε). Therefore, when the integrated circuit formed on the semiconductor substrate is energized for testing the logic circuit and generates heat from a defective portion, it is difficult to detect a temperature difference between the heat generating portion and the non-heat generating portion. In addition, the sample having a metal such as aluminum on the surface has a low emissivity, and has the same problem. In such a case, in the method of applying a black body paint to the surface of the observation sample and observing the same, in the case of observation using visible light, the pattern becomes invisible because the color becomes a single black color.

Therefore, a substance that transmits visible light and has a relatively high emissivity, such as oil, is applied to the observation surface. Observation by infrared rays in the state where such a substance is applied, if there is a defective part and heat is generated therefrom, the heat is transmitted to the substance applied to the surface, radiating infrared rays and observing with infrared rays, It can also be observed with light.

Next, the operation of the apparatus when observing a semiconductor substrate by the apparatus system of the present embodiment shown in FIG. 2 will be described. The above-described coating material is applied to a portion to be an observation region of a semiconductor substrate (10) as a sample, and the sample table 5
The semiconductor substrate 10 is placed on the sample, and the operator operates the computer 9 to move the sample moving stage 6 to move the semiconductor substrate to an approximate position. Next, the operator operates the computer 9 to move the one-axis stage 4 to move the visible light camera 2 to the visible light observation position.
Since the image from the visible light camera 2 is displayed on the monitor 901 in real time through the frame memory 903, the monitor 901 observes the semiconductor substrate 10 and focuses on the vertical movement mechanism attached to the sample table 5.
The operator adjusts the position to be observed by operating the computer 9, and stores the visible light image at this time in the frame memory 903.
To memorize.

Next, the one-axis stage 4 is moved by operating the computer 9 to move the infrared camera 1 to the infrared observation position. The screen displayed on the monitor 901 is automatically switched to the infrared image from the infrared camera 1. At this time, since the focus is adjusted so as to be the same as that of the visible light camera 2, it is not necessary to perform focusing by the vertical movement mechanism. In this manner, the semiconductor substrate 10 can be observed with infrared rays. Then, in order to identify the position of the infrared image in the sample, the infrared image is displayed by being superimposed on the visible light image stored in the frame memory 903 as described above. At this time, the infrared image is displayed in a yellow or red color on a portion having a certain output or more, and a visible light image is displayed on a portion having a certain output or less. This indicates that the colored portion is hotter than its surroundings. Further, the infrared image and the visible light image may be simply added and displayed. Further, the infrared image and the visible light image may be displayed separately on the monitor 901. In this way, by superimposing and displaying the infrared image and the visible light image,
The position of the heat generating portion in the integrated circuit on the semiconductor substrate detected by infrared rays can be identified.

In some cases, it is desired to change the observation position with the infrared camera 1 as described above. In such a case,
An operator determines an observation range (area) in advance. As shown in FIG. 3, the computer 9 uses a visible light camera to include a 3 × 3 screen (in accordance with the observation range,
Image information of 4 × 4, 4 × 3 screens, etc.)
03 is stored in advance. Next, the operator switches to the infrared camera, and the observation position is, for example, 30a or 30b in FIG.
Even when the stage is stopped at the position, the computer 9 superimposes the visible image and the infrared image at the arbitrary position based on the image information stored in advance and displays the image. At this time, when the observation position is 30a, the computer 9 cuts out image information of a predetermined area from each of the previously stored visible images 31a, 31b, 31c, 31d based on the stage position, and corresponds to the observation position 30a. A single visible screen is formed and displayed on the infrared screen. With such a system, an image in which an infrared image and a visible image are superimposed can be viewed at an arbitrary portion within a predetermined observation region.

In addition to the above-mentioned system, the following system is also conceivable. For example, the apparatus is provided with a stage position set button and a play button, and any observation position,
For example, (x, y) = (a1, b1), (a
2, b2), (a3, b3), and (a4, b4), the stage positions are sequentially set. 40a, 4
Reference numerals 0b, 40c, and 40d indicate observation areas at respective stage positions. The computer 9 stores each stage position in the frame memory 903 in correspondence with the visible light image at that position. Then, after switching to the infrared camera, when the operator presses the play button, the computer 9 automatically moves the stage to each set observation position, and superimposes the visible image and the infrared image at each position. Control may be performed so as to be displayed sequentially. Further, each image may be displayed on one screen.

[0027]

According to the first to fifth aspects of the present invention, it is possible to simultaneously observe an infrared image and a visible light image at the same position of a sample to be observed, and to determine the position of the infrared image in the sample. Can be easily identified.

Further, according to the invention of claim 6, even if the sample is an object having a low infrared emissivity such as silicon, the infrared radiating portion such as the heat generating portion of the sample can be clearly displayed and visible. Observation with light is also possible.

[Brief description of the drawings]

FIG. 1 is a view showing a sample observation microscope apparatus according to the present embodiment, wherein FIG. 1 (a) is a front view thereof, and FIG. 1 (b) is a side view thereof.

FIG. 2 is a diagram showing a system configuration of a microscope sample observation device of the present embodiment.

FIG. 3 is a diagram illustrating a system for simultaneously displaying a visible image and an infrared image.

FIG. 4 is a diagram illustrating another system for simultaneously displaying a visible image and an infrared image.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Infrared camera 2 Visible light camera 4 Single axis stage (moving mechanism) 5 Sample stand 6 Sample moving stage (sample moving mechanism) 9 Personal computer 10 Sample 901 Monitor (display means) 903 Frame memory (Storage means)

Claims (6)

[Claims] 1. An infrared camera that detects infrared rays and outputs an image signal, a visible light camera that detects visible light and outputs an image signal, and a sample in which the infrared camera and the visible light camera are observation targets. A sample observation device, comprising: a moving mechanism that moves the infrared camera and the visible light camera so as to observe the same place. 2. A storage device for storing image signals from the infrared camera and the visible light camera, and an image display device for displaying an image based on the two stored image signals. The apparatus of claim 1 comprising: 3. A storage means for storing an image signal from one of the infrared camera and the visible light camera, and an image based on the stored image signal and an image from the other of the infrared camera and the visible light camera. 2. The apparatus according to claim 1, further comprising: image display means for displaying an image based on a signal. 4. The moving mechanism includes a one-axis stage,
4. The apparatus according to claim 1, wherein said one-axis stage moves said infrared camera and said visible light camera while keeping them parallel to each other. 5. A sample moving mechanism for moving the sample, wherein the storage unit stores an image signal of the visible light camera or an image signal of the infrared camera at a first observation position of the sample. 5. The apparatus according to claim 2, wherein an image based on the stored image signal is displayed when an observation position of the sample is changed from a first observation position to a second observation position by the sample moving mechanism. 6. A sample to be observed is coated with a substance that transmits visible light and has a high emissivity of infrared light, and the sample is observed using the microscope apparatus according to any one of claims 1 to 5. How to observe.