JP2000269291A - Semiconductor device for non-destructive inspecton, its manufacture, and method and device for non-destructive inspection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a short defect while no electrical connection is required. SOLUTION: A thermo-electromotive force generating structure 21 is formed in a semiconductor device wafer 40. The thermo-electromotive force generating structure 21 is connected to first layer wirings 34a and 34b which are to be inspected. If a short defect 42 is present between the wirings, a thermo- electromotive force developed when the thermo-electromotive force generating structure 21 is irradiated with a laser beam 3 allows a current to flow through the short defect 42. The magnetic field induced by the current is detected with a magnetic field detector, and the detection result is, for example, displayed in brightness on an image display device corresponding to scanning of the laser beam 3, providing a scan magnetic field image. A laser scan microscope image from a reflection light is provided at the same time, or sequentially, with the scanning of the laser beam 3, with two images displayed superimposed. From this picture, the position of the short defect 42 is specified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for nondestructively inspecting a chip of a semiconductor device, and more particularly to a semiconductor device for nondestructively inspecting a chip, a method for manufacturing the same, a method for nondestructively inspecting the semiconductor device, and The present invention relates to a nondestructive inspection device.

[0002]

2. Description of the Related Art Conventionally, this type of non-destructive inspection technology has been disclosed in, for example, the 132nd meeting of the 132nd meeting of the 132nd Committee of the Japan Society for the Promotion of Science's Application of Charged Particle Beams published on November 30, 1995. "OBIC analysis technology using thermoelectromotive force" (Toru Koyama, Yoji Mashiko, Masahiro Sekine, Hiroshi Koyama, 199
5.11.30-12.1. Pp. 221-226), as shown in the description on the right column of page 221 in the fifth to first lines from the bottom and in FIG. 2, as a part of the failure analysis and the failure analysis of the semiconductor device, the thermal electromotive force of the wiring system is generated. It is used for non-destructively detecting defective parts.

FIGS. 13 and 14 are configuration diagrams showing an example of a conventional nondestructive inspection apparatus. A laser beam 3 generated by a laser generator 1 and narrowed down by an optical system 2 is scanned over a region to be observed on a semiconductor device chip 4. The scanning is controlled by the control / image processing system 106 and is performed by deflection by the optical system 2. The current generated at that time is supplied to the bonding pad 14-
1 is taken out by the prober 115-1 that has been probed. This current is detected by a current change detector 131, and is controlled on the image display device 7 by the control / image processing system 106.
The current value change is displayed as an image as a luminance change corresponding to the scanning location. This image is called a scanning current change image.

FIG. 13 shows a bonding pad 14-2 other than the bonding pad 14-1 connected to the current change detector 131 so that the generated current flows in a closed circuit.
Is a configuration example in the case where the prober 115-2 is probed and grounded. On the other hand, FIG. 14 shows the bonding pad 14 connected to the current change detector 131 so that the generated current flows only as a transient current in the open circuit.
This is an example of a configuration in which all bonding pads other than -1 are open. In order for a transient current to flow in an open circuit, a capacitance component is necessary. In this case, the capacitance component is a parasitic capacitance on a chip and a stray capacitance of a measurement system.

Next, the operation will be described. As described above, the difference between FIG. 13 and FIG. 14 is only the difference between whether a closed circuit is formed or an open circuit is formed. Under the control of the control / image processing system 106, the laser beam 3 generated by the laser generator 1 and narrowed down by the optical system 2 scans the region to be observed on the semiconductor device chip 4. Corresponding to the scanning, the scanning current change image is displayed on the image display device 7 in such a manner that, for example, the current flowing into the current change detector 131 is brightened, and the current in the opposite direction is darkened. At this time, gradation is displayed for both light and dark.

[0006] When the laser beam 3 is irradiated near the defect generating the thermoelectromotive force by the scanning of the laser beam 3,
At that moment, a thermoelectromotive force is generated and a current flows. At the moment when such a defect-free portion is irradiated, no thermoelectromotive force is generated and no current flows. Therefore, an image having a contrast of light and dark, that is, a scanning current change image is displayed on the image display device 7 only in the vicinity of the presence of the defect. It is to be noted that voids, foreign matters, disconnection, and the like are known as physical causes of the defect that generates this kind of thermoelectromotive force.

When obtaining the scanning current change image, a scanning laser microscope image which is an optical reflection image corresponding to laser scanning is obtained at the same time or before or after the scanning laser microscope image. After acquiring the scanning current change image and the scanning laser microscope image, the two images are superimposed by a well-known image processing function to create an image. It can be clearly recognized on the laser microscope image. The detection accuracy of the defect position by this technique is of the order of submicron.

In order to clearly know the type and the cause of the defect detected nondestructively in this way, usually, this point is physically destructively analyzed by using a focused ion beam method or an electron microscope. Conversely, this type of conventional technology enables non-destructive and precise confirmation of the location of defects with sub-micron accuracy, enabling efficient physical analysis of sub-micron sub-micro defects. Become. Thus, the prior art is in an important position in a series of analysis procedures for failure analysis and failure analysis.

Although only one chip is shown in FIGS. 13 and 14 for simplicity, the same probing is performed when one chip is selected and inspected in a wafer state.

[0010]

The first problem of the prior art is that the inspection can be performed only after the pre-process in the semiconductor device manufacturing process is completed and the bonding pad 14 is completed. That is. That is,
In the prior art, in order to detect a change in current, an electrical connection is always required between the inspection device and the semiconductor device, and therefore, the bonding pad 14 must be completed. The second problem is that short defects cannot be detected. That is, as described above, a void, a foreign substance, a disconnection, and the like can be detected, but a short circuit between wirings cannot be detected. If a defect that generates thermoelectromotive force happens to be present on the same wiring as the short defect, a short defect can also be detected indirectly, but the probability that such two types of defects exist on the same wiring is Extremely low.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to eliminate the need for electrical connection for inspection and perform inspection regardless of whether or not bonding pads are completed. An object of the present invention is to provide a semiconductor device for nondestructive inspection, a method for manufacturing the same, and a nondestructive inspection method and a nondestructive inspection device, which can be performed and detect a short defect.

[0012]

According to the present invention, there is provided a semiconductor device including first and second conductors disposed in close proximity on a semiconductor substrate. And a first connecting the one end of the thermoelectric generator to the first conductor.
And a second wiring connecting the other end of the thermoelectric generator and the second conductor.
Further, the present invention is a method of manufacturing a semiconductor device including first and second conductors disposed close to each other on a semiconductor substrate, wherein a thermoelectric generator is disposed on the semiconductor substrate. Connecting one end of the thermoelectromotive force generator to the first conductor by a first wiring, and connecting the other end of the thermoelectromotive force generator to the second conductor by a second wiring. It is characterized by doing.

According to another aspect of the present invention, there is provided a thermoelectric generator including first and second conductors disposed in close proximity on a semiconductor substrate, wherein the thermoelectric generator is disposed on the semiconductor substrate; A semiconductor device including a first wiring connecting one end of a generator and the first conductor, and a second wiring connecting the other end of the thermoelectric generator and the second conductor. A non-destructive inspection method, irradiating the thermoelectromotive force generator with laser light, detecting a magnetic field generated when irradiating the thermoelectromotive force generator with the laser light, the detection result of the magnetic field Based on this, it is characterized in that the presence or absence of a short-circuit defect relating to the first and second conductors is determined.

According to another aspect of the present invention, there is provided a thermoelectric generator including first and second conductors disposed in close proximity on a semiconductor substrate, wherein the thermoelectric generator is disposed on the semiconductor substrate; A semiconductor device including a first wiring connecting one end of a generator and the first conductor, and a second wiring connecting the other end of the thermoelectric generator and the second conductor. A non-destructive inspection device, a laser light irradiating means for irradiating the thermoelectromotive force generator with laser light, and a magnetic field detection for detecting a magnetic field generated when the thermoelectromotive force generator is irradiated with the laser light Means.

In the present invention, when a short-circuit defect exists between the first and second conductors, the thermo-electromotive force generating structure is generated when the thermo-electromotive force generating structure formed on the semiconductor substrate is irradiated with laser light. A current flows through the first and second conductors and the first and second wirings due to the thermoelectromotive force, and a magnetic field is generated. Therefore, by detecting this magnetic field with a magnetic field detecting means such as SQUID, the presence of a short defect can be detected. As described above, according to the present invention, it is possible to detect a short-circuit defect, which is impossible with the conventional inspection technology based on thermoelectromotive force. Moreover,
The inspection can be performed on the semiconductor substrate constituting the semiconductor device in a non-contact manner, so that the inspection can be performed even before the bonding pads are formed on the semiconductor substrate.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. [First Embodiment] FIG. 1A is a block diagram showing an example of a nondestructive inspection apparatus according to the present invention, and FIG. 1B is an example of a semiconductor wafer including chips constituting a semiconductor device according to the present invention. It is a partial expanded sectional side view which shows a to-be-inspected part. In the drawing, the same elements as those in FIGS. 13 and 14 are denoted by the same reference numerals. In the following, with reference to these drawings,
An example of a non-destructive inspection semiconductor device and a non-destructive inspection device of the present invention will be described, and at the same time, an embodiment of a method of manufacturing a non-destructive inspection semiconductor device and a non-destructive inspection device will be described.

First, the configuration of the nondestructive inspection device 102 shown in FIG. A semiconductor device wafer 40 is irradiated with a laser beam 3 emitted from a laser generator 1 and narrowed down by an optical system 2, and a magnetic field generated at that time is detected by a magnetic field detector 5. The laser beam 3 is two-dimensionally scanned to obtain an image. The scanning of the laser beam 3 is performed by deflecting the laser beam 3 inside the optical system 2. The scanning of the laser beam 3 may be equivalently performed by moving the semiconductor device wafer 40 instead of scanning the laser beam 3, and in this case, a wafer (not shown) on which the semiconductor device wafer 40 is mounted Stage is mechanically moved. The output of the magnetic field detector 5 is controlled
The image processing system 6 (image generating means according to the present invention) performs luminance display or pseudo-color display on the image display device 7 in correspondence with the scanning position, and obtains a scanning magnetic field image corresponding to a scanning current change image in the related art.

Next, the semiconductor device wafer 40 will be described with reference to FIG. In the semiconductor device wafer 40, first-layer wirings 34a and 34b are formed on a silicon substrate 31 via an insulating layer 32 in a manufacturing process, and vias 35 respectively connected to these wirings are formed.
a, a via 35b is formed. On the silicon substrate portion 31, contact portions 33 are erected at two places, and a first layer wiring 34 is formed.
The lower surfaces near the ends of a and 34b are connected to the upper ends of the contact portions 33, respectively. The vias 35a and 35b are
In the present embodiment, the first-layer wirings 34a and 34b are erected on the upper surface near the end opposite to the connection point with the contact portion 33.

The insulating layer 32 is formed on the first-layer wirings 34a and 34b, and the second insulating layer 32 is formed on the first-layer wirings 34a and 34b.
Instead of forming a layer wiring, a wiring 20 for forming a thermoelectromotive force generating structure is formed. The wiring 20 extends between the vias 35a and 35b.
Connect to the upper end of 35b. A thermo-electromotive force generating structure 21 (thermo-electromotive force generator) is interposed in the middle of the wiring 20.

The first-layer wirings 34a and 34b extend substantially in a straight line in plan view. In the present embodiment, the short-circuit defect 42 exists between opposing ends, and
It is assumed that the layer wirings 34a and 34b are electrically short-circuited due to the short defect 42. When the laser beam 3 is applied to the thermoelectromotive force generating structure 21, a thermoelectromotive current flows through a closed circuit including the short defect 42 along a path indicated by an arrow 61. The magnetic field generated by this current is detected by the magnetic field detector 5 shown in FIG.

Next, the operation will be described. First, the operation of the non-destructive inspection device 102 will be described with reference to FIG. The laser generated from the laser generator 1 is narrowed down by the optical system 2, and is irradiated as a laser beam 3 on the semiconductor device wafer 40. As the laser used here, a He-Ne laser having a wavelength of 633 nm, a He-Ne laser having a wavelength of 1152 nm, a laser diode having a wavelength of about 1300 nm, a YLF (ylf) laser having a wavelength of about 1300 nm, and the like are convenient. . Optical system 2
Is performed by deflecting the laser beam 3 vertically and horizontally using a galvanomirror, an acousto-optic device, an electro-optic device, or the like. When the scanning area is large, it is better to fix the irradiation point of the laser beam 3 and the magnetic field detector 5 and move the semiconductor device wafer 40 side instead of scanning the laser beam 3 to always generate a magnetic field. This is convenient because the magnetic field can be detected at the strongest position. The laser beam 3 irradiates the semiconductor device wafer 40 while being scanned, and the thermoelectromotive current flows while irradiating the thermoelectromotive force generating structure 21 and being connected to the thermoelectromotive force generating structure 21. Only when the current wiring has a short-circuit defect 42 and a closed circuit current flows as described later with reference to FIG.

Normally manufactured semiconductor device wafer 4
There is no place on 0 that generates a detectable thermoelectromotive force. When the semiconductor device wafer 40 includes voids as described above, a thermoelectromotive force will be generated,
This does not particularly hinder the detection of the short defect 42 in the present embodiment.

Thermoelectromotive force generating structure 2 by laser beam 3
1 is irradiated, and when a thermoelectromotive current flows, a magnetic field is induced, and the magnetic field detector 5 detects this magnetic field. (1) SQUID (Supercon)
ducting Quantum Interfere
nce Device: superconducting quantum interference device) magnetometer,
(2) fluxgate magnetometer, (3) nuclear magnetic resonance magnetometer, (4) semiconductor magnetic sensor (Hall element)
Although the type is known, the SQUID has an ultra-high sensitivity measurement range from 1 fT (femtotesla) to 10 nT (nanotesla), whereas the fluxgate magnetometer and the nuclear magnetic resonance magnetometer have 0.1 nT. The semiconductor magnetic sensor has a measurement area from (nano Tesla) to 0.1 mT (milliTesla) and the measurement area from 1 nT (nanoTesla) to 1T (Tesla), and the sensitivity is lower than that of SQUID. According to the results of experiments performed by the inventors of the present invention to date,
Only the SQUID is a magnetic field detector 5 having a sensitivity enough to detect a magnetic field generated by a thermoelectromotive current when the thermoelectromotive force generating structure 21 formed in the semiconductor device wafer 40 is irradiated with a laser.

In the following example, only the case where the high-temperature superconducting SQUID is used is shown from the viewpoint of cost and ease of handling, but if higher sensitivity is required, the low-temperature superconducting SQUID is used.
May be used. Returning to the description of the operation with reference to FIG. When the magnetic field detector 5 detects the magnetic field and outputs a signal having a magnitude corresponding to the strength of the detected magnetic field, the control / image processing system 6 converts the signal into a luminance signal and supplies the luminance signal to the image display device 7. , An image corresponding to the scanning position is displayed. When a sufficient S / N (signal-to-noise ratio) cannot be obtained by one scan, the images obtained by a plurality of scans may be integrated.
If a sufficient S / N cannot be obtained, the S / N can be greatly improved by modulating the laser beam 3 and amplifying the signal with a lock-in amplifier.

Next, a description will be given with reference to FIG.
When the thermoelectromotive force generating structure 21 is irradiated with the laser beam 3, as shown by the arrow 61, the thermoelectromotive force generating structure 21-
Via 35a-Short defect 42-First layer wiring 34b-
A thermoelectromotive current flows in a closed circuit of the via 35b and the thermoelectromotive force generation structure 21. Such a closed circuit current flows only when the short defect 42 exists. Short defect 4
2 does not exist, a transient open-circuit current flows. This current has a time constant determined by the parasitic capacitance and resistance and a time constant determined by the irradiation time of the laser beam 3, and the closed-circuit current It will decay in a very short time compared to. Therefore, the magnetic field due to the current flowing through the closed circuit when the short defect 42 exists is much stronger and has a longer duration, so that the magnetic field generated by the transient current when the short defect 42 does not exist can be ignored.

When the short defect 42 exists, a current flows through the path indicated by the arrow 61 as described above.
A magnetic field is generated, and the magnetic field detector 5 detects this magnetic field. The following operation is as described above, and the signal that the magnetic field detector 5 detects and outputs the magnetic field is transmitted to the control / image processing system 6.
And the portion on the screen corresponding to the position of the thermoelectromotive force generating structure 21 is displayed with, for example, high brightness, and the first layer wiring 3
It can be seen that a short defect exists between 4a and 34b.

As described above, according to the present embodiment, it is possible to detect a short-circuit defect, which is impossible with the conventional inspection technique based on thermoelectromotive force. In addition, the inspection can be performed on the semiconductor device wafer 40 in a non-contact manner, and therefore, as shown in FIG.
The inspection can be performed even before the bonding pad is formed at 0.

Next, a specific example of the thermoelectromotive force generating structure 21 will be described. Metal materials such as aluminum, copper, and gold that are usually used in semiconductor devices have low thermoelectric power and are not suitable as materials for the thermoelectromotive force generating structure 21 in order to obtain a sufficient S / N ratio. Titanium silicide (TiSi) wiring (hereinafter Ti) formed on polysilicon (PolySi)
(Abbreviated as Si wiring) is also used as normal wiring,
According to the experimental results of the inventors of the present invention, a considerably large thermoelectric power is obtained, which is suitable for the thermoelectromotive force generating structure 21.

In order to generate a thermoelectromotive force, a temperature gradient is required, which will be described later in detail.
This can be realized by narrowing a part of the i-wiring and irradiating the vicinity thereof with the laser beam 3. Which part and how many thermoelectric power generation structures 21 are formed in the semiconductor chip depends on the situation where the target device is placed. At the early stage of development, if you install as many combinations as possible, short spots can be easily found and quick feedback is possible. If one or more short spots are found on any chip in the wafer, it is not necessary to proceed to the next step, and the cause of the short is analyzed and corrective measures are taken for the layout design and manufacturing process conditions that caused the short. After that, the manufacturing process may be performed again from the beginning. By adopting such a method, it is possible to take corrective action much earlier than performing a failure analysis by the conventional method after forming the bonding pad as in the conventional method.

However, in the case where a chip having no short-circuit portion in one chip exists in the wafer, in order to proceed to the next step, the thermoelectromotive force generating structure 21 and the wiring for forming the thermoelectromotive force generating structure are required. 20 needs to be removed. If there is a region on the chip that is not used as a function, such as a gate array, a dummy wiring and a thermoelectromotive force generating structure 21 are formed in that region, and the occurrence of short defects 42 in that region is monitored. By doing so, it can be determined whether to proceed to the next step. In this case,
The thermoelectromotive force generating structure 21 and the wiring 20 for forming a thermoelectromotive force generating structure can be left as they are to proceed to the next step, which is efficient.

If there is such an empty area, there is a more effective method. Instead of making the thermoelectromotive force generating structure 21 as a process other than the normal manufacturing process, the thermoelectromotive force generating structure 21 is formed in a vacant area in a part of the normal process to extend the wiring,
It is possible to adopt a method of connecting to the wiring (the first-layer wirings 34a and 34b in the example of FIG. 1) from which a short defect is to be detected. According to this method, since the thermoelectromotive force generating structure 21 is also formed in a normal process, the inspection can be performed without extra cost. This method will be described later in detail.

TEG (Test Element Gr)
(ups: test-only structure) can be applied more freely. Conventionally, for electrical testing of TEG,
A method of providing a probe for probing and performing a probe or a method of providing a bonding pad and taking out with a bonding wire has been adopted. However, as in the present embodiment, if a thermoelectromotive force structure is formed in a semiconductor chip and a thermoelectric current generated by laser irradiation is detected by a magnetic field detector 5, such a probing pad or a bonding pad The TEG can be electrically tested without providing the TEG. As a result, testing can be performed without forming bonding pads, etc., and the labor for probing can be reduced, thereby reducing test man-hours, thus reducing semiconductor device manufacturing costs, and significantly shortening semiconductor device manufacturing delivery time. It becomes possible to do.

It should be noted that the semiconductor device chip including the thermoelectromotive force generating structure 21 may be used alone or in a state formed on a semiconductor wafer. Can be detected. Therefore, the present invention is not limited to a semiconductor device chip in any state.

[Second Embodiment] Next, a second embodiment of the present invention will be described in detail with reference to the drawings. FIG. 2 is a block diagram showing a nondestructive inspection apparatus according to a second embodiment of the present invention, and FIG. 3A shows a portion to be inspected in an example of a semiconductor wafer including a chip constituting a semiconductor device according to the present invention. FIG. 2B is a partially enlarged cross-sectional side view, and FIG. In the figure, the same elements as those in FIG. 1 are denoted by the same reference numerals, and a detailed description thereof will be omitted here.

A non-destructive inspection semiconductor device and a non-destructive inspection device according to a second embodiment of the present invention will be described below with reference to these drawings. A method for manufacturing a semiconductor device for inspection and a nondestructive inspection method will be described.

First, the configuration of the nondestructive inspection device 104 according to the second embodiment will be described with reference to FIG. This non-destructive inspection device 104 differs from the non-destructive inspection device 102 of the first embodiment in that a laser beam 53 having a specific wavelength of 1.3 μm is generated by a laser generator 51 as a laser beam. And the point where the laser beam 53 is incident from the back surface 4b side of the wafer 44.

The reason for using a laser having a wavelength of 1.3 μm is as follows.
There are two. The first two of them are based on the fact that the substrate portion of the target semiconductor device is often made of silicon (Si). The first reason for using a laser having a wavelength of 1.3 μm is that a laser beam 53 is irradiated from the back surface of the chip, and the surface 4f can be heated by the laser beam 53 transmitted through the substrate. The reason that irradiation from the back of the chip is important is that it is difficult to heat many of the wiring parts only by irradiation from the front of the chip in many current semiconductor devices, and irradiation from the back is often required It is. The reason that it is difficult to heat most of the wiring part only by irradiation from the chip surface is that the multilayer wiring structure is common, the upper wiring is usually wider and often covers the lower wiring, When a device is mounted, it is often the case that the chip surface is directed to the mounting substrate surface, or a structure is used in which the chip surface is covered with leads during packaging.

Since a laser having a wavelength of about 1.1 μm or more transmits through a low concentration of silicon used as a substrate to a considerable extent, it is irradiated from the back surface of the semiconductor device wafer 44 to heat a wiring portion near the front surface. It is possible to For example, when a 1152-nm He-Ne laser is used, a P- (P-minus) substrate has a wafer thickness of 625 μm.
In the case of m, it transmits about 50%. For these reasons,
By using a laser having a wavelength of 1.1 μm or more, the wiring near the front surface can be heated by irradiating from the back surface of the chip without polishing the wafer specially.

The second reason for using a laser having a wavelength of 1.3 μm is as follows.
The third is the OBIC current (Optical Beam I
This is to prevent the occurrence of n.sub.current (optical excitation current). When silicon is irradiated with a laser having a wavelength of about 1.2 μm or less, an OBIC current is generated,
This becomes noise with respect to the thermoelectromotive current. For example,
Using the above 1152 nm (1.076 eV) He-Ne laser, the distance between the valence band and the conduction band of silicon (1.1
Since no electron-hole pair is generated with the 2eV) transition,
When the impurity does not exist or is small, the OBIC current is not generated or small. However, in a region where As, B, P, or the like having a concentration enough to form a transistor is present as an impurity, a transition via these impurity levels requires an energy of 1.076 eV or less.
The OBIC current is generated to the extent that the C current is required for detection, and this OBIC current becomes noise with respect to the thermoelectromotive force current. In order to prevent such noise due to the OBIC current, 1.2 μm
It is necessary to use a laser having the above wavelength.

The third reason for using a laser having a wavelength of 1.3 μm is as follows.
Third, the shorter the wavelength, the narrower the laser beam 3 can be narrowed, so that the resolution of the scanning laser microscope image and the scanning magnetic field image is improved. For the above three reasons, a laser with a wavelength of 1.2 μm or more and as short as possible is preferred. Under these conditions, a laser that can be practically used is 1.3 μm
Was selected. Specifically, a 100 mW laser diode is reasonable. If it is desired to increase the thermoelectromotive force current by increasing the laser irradiation power, a 500 mW YLF (ylf) laser can be used.

On the other hand, there are two reasons why the laser beam 53 is incident from the back side of the semiconductor device wafer 44. The first reason is that, as described above, it is difficult to heat most of the wiring portions only by irradiation from the chip surface, and therefore, laser beam irradiation from the chip back side is effective. The second reason is that when the magnetic field detector 5 is arranged on the chip surface side, the distance between the path of the thermoelectromotive current and the magnetic field detector 5 becomes shorter, and the magnetic field detected by the magnetic field detector 5 becomes larger. This means that a smaller thermoelectromotive current can be detected. Thus, it is better to irradiate the laser beam 53 from the back side of the chip for originally different reasons.
It is better to arrange the magnetic field detector 5 on the chip surface side, but as a result, it is arranged on the opposite side, so that the configuration is easy.

Next, the configuration of the semiconductor device wafer 44 to be inspected will be described with reference to FIG. In addition,
The semiconductor device wafer 44 shown in FIG. 3A is an enlarged view of a part of the semiconductor device wafer 44 of FIG. 2, but is shown upside down from FIG.
FIG. 3B shows only particularly important elements in FIG. 3A. Note that FIG.
In the figure, a portion that is originally hidden due to the overlap is shown by a solid line without using a broken line. The following description focuses on the differences from the first embodiment. In the present embodiment, the laser beam 53 having a wavelength of 1.3 micrometers is used, and the laser beam 53 is incident from the back surface 4b side of the wafer 44, as described above. As shown in FIG. 3B, even if the laser beam 53 enters from the back side, the thermoelectromotive force generating structure 21
The position of the thermoelectromotive force generation structure 21 is shifted from the center of the thermoelectromotive force generation structure forming wiring 20a so that the first-layer wiring 34b and the thermoelectromotive structure 21 do not overlap. Further, the width of the thermoelectromotive force generating structure forming wiring 20a is wider than the width of the first layer wiring 34b. The reason will be described later.

Next, the operation of the second embodiment will be described focusing on the differences from the above embodiment. First, a supplementary explanation about the use of a laser having a wavelength of 1300 nm will be given. The diameter of the laser beam, which determines the spatial resolution, can be selected over a wide range by selecting the objective lens, but the minimum diameter is limited to the wavelength by the diffraction limit. A confocal function may be provided in the optical system, or NA (Numerical A)
With the use of an objective lens having a large numerical aperture, a spatial resolution of a scanning laser microscope image of about 400 nm can be easily realized with a 633 nm laser, and a resolution of about 800 nm can be easily realized with a 1300 nm laser.

The resolution of the important image in the scanning magnetic field image is not usually the resolution of the scanning magnetic field image itself, but the resolution of the scanning laser microscope image in the same area as the scanning magnetic field image. The position recognition accuracy of the power generation structure is determined. The reason will be described below. In order to detect the position of the thermoelectromotive force generating structure corresponding to the short-circuit defect,
The scanning laser microscope image and the scanning magnetic field image are superimposed by a well-known image processing function.
At 56 gradations, the scanning magnetic field image is displayed in red. The contrast of the scanning magnetic field image can be adjusted to be narrowed down to the size of one pixel having the highest intensity, and this size can be much smaller than the spatial resolution of the scanning laser microscope image.

By displaying the scanning magnetic field image narrowed down to the contrast of one pixel and the scanning laser microscope image as a superimposed image, the thermoelectromotive force generating structure corresponding to the short-circuit defect is included in the scanning laser microscope image. Can be clearly recognized. In order to adopt such a position recognition method, the recognition accuracy of the position of the thermoelectromotive force generating structure corresponding to the short defect is determined by the spatial resolution of the image of the scanning laser microscope. The following points are important in relation to the spatial resolution of the scanning laser microscope image. As described above, the photo-induced current (OB
IC current: Optical BeamInduced
(Current) causes noise, and it is difficult to detect the thermoelectromotive force current itself.
It is desirable to use a 300 nm laser. As described above, a method of irradiating the laser from the back of the chip is also effective, taking advantage of another feature of the 1300 nm laser, that is, the advantage that the attenuation in silicon is small.

As described above, the 1300 nm laser has a great advantage, but when using a 1300 nm laser, a problem is the spatial resolution. From the viewpoint of the spatial resolution of a scanning laser microscope image, a laser having a short wavelength such as 633 nm is desirable. To solve this dilemma,
For example, the following method is effective. As a laser generator, a 633 nm He-Ne laser and 1300 nm
(YLF) laser is used. Then, a laser having a wavelength of 633 nm is used for acquiring a scanning laser microscope image, and a laser having a wavelength of 1300 nm is used for acquiring a scanning magnetic field image, and the obtained two images are superimposed and displayed.

When a 1300 nm laser is irradiated from the back surface, a 633 nm scanning laser microscope image used for superimposition is taken from the front surface, converted into a mirror image, and then superposed. According to this method, the detection position accuracy of the thermoelectromotive force generating structure corresponding to the short-circuit defect is doubled as compared with the case where only the 1300 nm laser is used. This method is effective because the superposition accuracy is higher than the spatial resolution. Further, when the position cannot be clearly recognized only by the scanning laser microscope image from the front surface, the three images may be superimposed together with the scanning laser microscope image from the rear surface. An improvement effect is seen depending on the position of the thermoelectromotive force generating structure corresponding to the short-circuit defect.

If the spatial resolution of the scanning laser microscope image from the back side is insufficient with a laser of 1300 nm, a laser with a short wavelength can be used by reducing the attenuation by making the wafer thinner. For example, if the wafer thickness is reduced to 15 micrometers, 633n
Since even a laser having a wavelength of m transmits 60% or more, it is possible to obtain a high spatial resolution scanning laser microscope image from the back surface. However, even in such a case, if the configuration of the inspection object is such that the OBIC current causes noise, that is, if the current path is a path including a silicon part instead of only a wiring part, However, it is necessary to obtain a scanning magnetic field image by inducing a long-wavelength laser that does not generate an OBIC current.

Next, the operation as viewed from the inspected side will be described with reference to FIG. In the present embodiment, FIG.
As shown in (B) of FIG.
The width of 0a is widened, and the reason is as follows. When the thermoelectromotive force generating structure 21 is irradiated with the laser beam 53, as in the case of the first embodiment, the thermoelectromotive force generating structure 21-wiring 20a-via 35a-short defect 42
The first layer wiring 34b, the via 35b, the wiring 20a, and the thermoelectromotive force current flow through the closed circuit path of the thermoelectromotive force generating structure 21.

As shown in FIGS. 3A and 3B, the current path is divided into the current path 611 on the first layer wiring 34b side and the current path 611 on the thermoelectromotive force generating structure forming wiring 20a side. The current path 612 is considered separately. The current path 611 is relatively narrow, and the magnetic field generated by the current is also localized along the wiring. On the other hand, since the current path 612 is distributed over a relatively wide range, the magnetic field induced by the current spreads over a wide range. The magnetic fields generated in the current path 611 and the current path 612 have directions almost cancel each other as directions outside the closed circuit loop, but do not cancel out so much because the distribution regions of the magnetic field are different as described above. , As a magnetic field. In the case where the width of the wiring for which the short defect 42 is to be detected is not narrow but wide, the wiring 20 for forming the thermoelectromotive force generating structure is contrary to this example.
What is necessary is just to make a thin.

Next, a specific example of the thermoelectromotive force generating structure 21 will be described. According to the result of the experiment by the inventors of the present invention, the TiSi wiring is
If a portion is formed so as to have a small width, the narrowed portion can be used as the thermoelectromotive force generating structure 21. This is because, in addition to this TiSi having a large thermoelectric power, by narrowing a part of the width, the heat conduction of the part is deteriorated, and when a laser beam 53 is irradiated, a large temperature gradient and It is considered that the right and left imbalance of the temperature gradient is easily made, and as a result, a large transient thermoelectromotive force and a current accompanying it are generated.

In the experiments conducted so far by the inventors of the present invention, a laser beam having a diameter of 0.4 μm and an irradiation power of about 3 mW is irradiated on a thermoelectromotive force generating structure 21 made of TiSi wiring. A voltage due to a thermoelectromotive force of about 10 mV is obtained. This voltage value is the high-temperature superconducting SQ
This is a value that allows a current sufficient to generate a magnetic field that can be detected using the UID. In addition, the thermoelectromotive force generation structure 21
Can be integrally formed with the wiring as a part of the wiring 20a for forming a thermoelectromotive force as described above.
It is also possible to separately form the thermoelectromotive force generating structure 21 and the wiring connecting the thermoelectromotive force generating structure 21 to the object to be inspected using different materials.

[Third Embodiment] Next, a third embodiment of the present invention will be described. FIG. 4A is a partially enlarged cross-sectional side view showing a semiconductor wafer including a chip constituting the semiconductor device for nondestructive inspection according to the third embodiment, and FIG. 4B is a partially enlarged plan view thereof. In the figure, the same elements as those in FIG. 1 are denoted by the same reference numerals, and a detailed description thereof will be omitted here.

The non-destructive inspection semiconductor device according to the third embodiment of the present invention will be described below with reference to these drawings, and at the same time, the non-destructive inspection semiconductor device according to the third embodiment will be described. The manufacturing method and the nondestructive inspection method will be described. As the nondestructive inspection device, for example, the nondestructive inspection device 104 shown in FIG. 2 can be used.

In the semiconductor device for nondestructive inspection according to the third embodiment, as shown in FIG. 4B, in the semiconductor device wafer 46 including the chips constituting the semiconductor device for nondestructive inspection, On the side of the first-layer wiring 34b, the first-layer wiring 34c is arranged in parallel with the first-layer wiring 34b at a distance substantially in parallel with the first-layer wiring 34b.

The first-layer wirings 34b and 34
In order to detect a short defect 42 between the points c and c, FIG.
As shown in (B), the thermoelectromotive force generating structure 21 is arranged near one end of the first-layer wirings 34b and 34c.
More specifically, the thermoelectric power generation structure forming wiring 2 is provided above one end of each of the first-layer wirings 34 b and 34 c via the insulating layer 32.
0 is formed, and a thermoelectromotive force generating structure 21 connected to the wiring 20 is formed between the two wirings 20. First layer wiring 3
Vias 35 are respectively provided on the upper surfaces of the one end portions of 4b and 34c.
The upper ends of the vias 35b and 35c are connected to the lower surface of the wiring 20, respectively.

Therefore, the semiconductor device wafer 4
In FIG. 6, for example, as shown in FIG.
When a short-circuit defect 42 exists on the end side of b and 34c opposite to the thermoelectromotive force generating structure 21, when the laser beam 53 irradiates the portion of the thermoelectromotive force generating structure 21, it is indicated by an arrow 61. Current flows through the path.

By detecting this current with a magnetic field detector, performing image processing and displaying the current, a scanning magnetic field image of a short defect location can be obtained. Therefore, in the third embodiment, the short defect 42 is detected. In a case where two wirings to be detected are arranged side by side at intervals, a short defect 42 extending in the width direction of the wiring can be detected, and the same as in the first embodiment. The effect can be obtained.

In addition, in the third embodiment, since the current flows through a closed circuit formed in a plane parallel to the wafer plane, the magnetic field is formed in the vertical direction, and the magnetic field can be easily detected from the outside. can do. Therefore, there is no need to perform structural work such as taking into account the width of the wiring as in the second embodiment. Further, in the third embodiment, as shown in FIG.
Since it can be arranged in the gap between the wirings 34b and 34c, it is possible to irradiate the laser beam 53 from the back surface side of the semiconductor device wafer 46 as shown in FIG.

[Fourth Embodiment] Next, a fourth embodiment of the present invention will be described. FIG. 5A is a partially enlarged sectional side view showing a semiconductor wafer including a chip constituting a nondestructive inspection semiconductor device according to a fourth embodiment, and FIG. 5B is a partially enlarged plan view of the same. In the figure, the same elements as those in FIG. 3 are denoted by the same reference numerals, and a detailed description thereof will be omitted here.

A non-destructive inspection semiconductor device according to a fourth embodiment of the present invention will be described below with reference to these drawings, and at the same time, a non-destructive inspection semiconductor device according to the fourth embodiment will be described. The manufacturing method and the nondestructive inspection method will be described. As the nondestructive inspection device, for example, the nondestructive inspection device 104 shown in FIG. 2 can be used.

The fourth embodiment is different from the second embodiment in that the first layer wiring 34b connects different diffusion layers in the substrate portion 31 in the semiconductor device wafer 48. And the first layer wiring 34
The point is that a via connecting the b and the upper wiring is not originally provided. In order to connect the diffusion layers to each other, contact portions 33 connected to the diffusion layers are provided below both ends of the first-layer wiring 34b.

As described above, when the via connecting the first-layer wiring 34b and the upper wiring is not provided, as shown in FIG. 5, for example, on one end of the first-layer wiring 34b. Are provided with inspection vias 305. Thereby, the second
The structure can be equivalent to that of the semiconductor device wafer 44 of the second embodiment. As a result, the same inspection as that of the second embodiment can be performed, and the same effect as that of the second embodiment can be obtained. .

If the inspection via 305 is provided in a place where the upper layer wiring does not pass, after the inspection is completed, the thermoelectromotive force generation structure 21 and the thermoelectromotive force generation structure forming wiring 20 are removed, and the upper layer wiring is removed. Is formed, the inspection via 30
5 is not connected to the upper layer wiring, and the original function of the semiconductor device is not affected.

[Fifth Embodiment] FIG. 6A is a partially enlarged cross-sectional side view showing a semiconductor wafer including a chip constituting a nondestructive inspection semiconductor device according to a fifth embodiment. B) is a partially enlarged plan view of the same. In the figure, the same elements as those in FIG. 1 and the like are denoted by the same reference numerals, and a detailed description thereof will be omitted here.

The non-destructive inspection semiconductor device according to the fifth embodiment of the present invention will be described below with reference to these drawings, and at the same time, the non-destructive inspection semiconductor device according to the fifth embodiment will be described. The manufacturing method and the nondestructive inspection method will be described. As the nondestructive inspection device, for example, the nondestructive inspection device 104 shown in FIG. 2 can be used.

In the semiconductor device wafer 50 including the semiconductor chips constituting the semiconductor device for nondestructive inspection according to the fifth embodiment, the semiconductor device wafer 50 for forming a thermoelectromotive force generating structure shown in FIGS. Wiring 20 and thermoelectromotive force generating structure 21
Are formed in the same layer in the same manufacturing process as the first-layer wiring 34. The above-described TiSi is suitable as a material of the wiring 20 and the thermoelectromotive force generating structure 21.

The wiring to be inspected is a second-layer wiring,
In this example, the first layer wiring 3 is located above the first layer wiring 34.
4, a second-layer wiring 36a and a second-layer wiring 36b extend substantially parallel to each other with an insulating layer 32 interposed therebetween. In the figure, the second-layer wirings 36a and 36b further extend leftward, and these two wirings are electrically insulated from each other in the original function.

As shown in FIG. 6B, the thermoelectromotive force generating structure 21 is disposed between the second wiring 36a and the second wiring 36b, and The thermoelectromotive force generating structure forming wiring 20 connected to the thermoelectromotive force generating structure 21 extends. Inspection vias 305a and 305b are respectively set up on the wiring 20, and a second
In the same process as the layer wirings 36a and 36b, the inspection wiring 3
6c and 36d are formed. Inspection wiring 36c, 36d
Are separated from each other by a second layer wiring 36
a, 36b, and the inspection vias 305a, 305a,
65b.

After forming the second wiring, an insulating layer 32 is formed thereon, and the second layer wirings 36a and 36b penetrate the insulating layer 32, and the ends of the second layer wirings 36a and 36b on the side of the thermoelectromotive force generating structure 21; Inspection vias 305d, 305e, 305c, 30 are provided on the ends of the inspection wirings 36c, 36d on the wiring 36a, 36b side.
5f is formed.

Then, on the surface of the insulating layer 32, an inspection wiring 37b for connecting the inspection via 305d and the inspection via 305c is formed, and an inspection wiring for connecting the inspection via 305e and the inspection via 305f is formed. The wiring 37a is formed.
Therefore, even in this semiconductor device wafer 50, the second
When the short-circuit defect 42 exists between the layer wirings 36a and 36b, when the thermoelectromotive force generating structure 21 is irradiated with the laser beam 53 from the back surface side of the semiconductor device wafer 50, a current flows along a path indicated by an arrow 61. By detecting the magnetic field generated at that time, a magnetic field scanning image corresponding to the short defect 42 can be obtained. Therefore, the same effects as those of the first embodiment can be obtained in the fifth embodiment.

Further, in the fifth embodiment, the thermoelectric power generation structure forming wiring 20, the thermoelectromotive force generation structure 21, the inspection wirings 36c, 36d, etc. are the first layer wiring or the second layer wiring.
Since it can be formed in the same manufacturing process as the layer wiring, an increase in extra steps for forming a wiring for inspection and the like can be minimized. In this example, the extra manufacturing process for the inspection is a process of forming the inspection wirings 37a and 37b, which can be formed by wiring having a simple structure such as an aluminum wiring, and bothersomely generating the thermoelectromotive force. The increase in the number of steps is minimized as compared with the case where a TiSi wiring is newly manufactured as the structure forming wiring 20. Further, such inspection wirings 37a and 37b are also very easily removed after the inspection is completed. Further, the function of the semiconductor device is not affected. [Sixth Embodiment] FIG. 7A is a partially enlarged cross-sectional side view showing a semiconductor wafer including chips constituting a nondestructive inspection semiconductor device according to a sixth embodiment, and FIG. It is the same element enlarged plan view. In the drawing, the same elements as those in FIG. 6 and the like are denoted by the same reference numerals, and a detailed description thereof will be omitted here.

The non-destructive inspection semiconductor device according to the sixth embodiment of the present invention will be described below with reference to these drawings, and at the same time, the non-destructive inspection semiconductor device according to the sixth embodiment will be described. The manufacturing method and the nondestructive inspection method will be described. As the nondestructive inspection device, for example, the nondestructive inspection device 104 shown in FIG. 2 can be used.

The semiconductor device wafer 52 including the semiconductor chips constituting the semiconductor device for nondestructive inspection according to the sixth embodiment is different from the semiconductor device wafer 50 in that the inspection wiring is the second wiring of the wiring to be inspected. The point is that it is formed only on the same layer as the layer wiring. Semiconductor device wafer 52
However, the thermoelectromotive force generating structure forming wiring 20 and the thermoelectromotive force generating structure 21 are formed in the same step and in the same layer as the first layer wiring 34. The second layer wirings 36a and 36b are formed thereon via the insulating layer 32 as in the case of the semiconductor device wafer 50 shown in FIG. 6, but in the present embodiment, the second layer wirings 36a and 36b are formed. , 36b are formed longer than the original length, and the extended portions are formed as inspection wirings 36c, 36d. The inspection wirings 36c and 36d are extended to the upper part of the wiring 20, and the inspection vias 305 are respectively provided at the ends.
a, 305b are connected to the wiring 20.

Therefore, the semiconductor device wafer 5
9, inspection is performed in the same procedure as in the second embodiment, etc., and as shown in FIGS. 9A and 9B, a short defect 42 is present between the second-layer wirings 36 a and 36 b. If there is, when the thermoelectromotive force generating structure 21 is irradiated with the laser beam 53, a current flows through each wiring along the path indicated by the arrow 61, and the short defect 42 can be detected. Therefore, also in the sixth embodiment, the same effects as in the first embodiment can be obtained.

In the sixth embodiment, after the inspection, after the boundaries 38a, 38b between the second-layer wirings 36a, 36b and the inspection wirings 36c, 36d shown in FIG.
The inspection wirings 36c and 36d are removed, and as a result, the semiconductor device wafer 52 is in the state shown in FIGS. 8A and 8B (corresponding to FIGS. 7A and 7B, respectively).

As described above, in the present embodiment, only the extension of the second-layer wirings 36a and 36b is formed as the inspection wiring, and therefore, compared to the fifth embodiment described above. The process is very simple. Of course, inspection wiring 36
Removal of c and 36d is also easy.

Further, in this embodiment, it is not necessary to form a wiring or the like for inspection on the second second-layer wirings 36a and 36b which are wirings to be inspected. The inspection can be performed immediately after the layer wirings 36a and 36b are formed. In addition, as shown in FIGS. 9A and 9B, a closed circuit formed by the short-circuit defect 42 is simple as a whole, and the current path indicated by the arrow 61 is simple. Detection of a magnetic field becomes easy, and a good magnetic field scanning image can be obtained.

[Seventh Embodiment] FIG. 10A is a conceptual diagram showing a layout on a chip constituting a semiconductor device according to a seventh embodiment as a block.
(B) is a conceptual diagram showing a block that is repeated in (A) and showing the internal structure and the connection relationship between them. In the figure, the same elements as those in FIG. 1 are denoted by the same reference numerals.

Hereinafter, a semiconductor device for nondestructive inspection and a method for manufacturing the semiconductor device for nondestructive inspection according to the seventh embodiment of the present invention will be described with reference to these drawings. The inspection of the semiconductor device for nondestructive inspection according to the seventh embodiment is performed by the nondestructive inspection method described as the first embodiment using, for example, the nondestructive inspection device 102 shown in FIG. be able to.

The semiconductor device wafer 54 constituting the semiconductor device for nondestructive inspection of the seventh embodiment is different from that of the above embodiment in that the inspection tool region 120 including the thermoelectromotive force generating structure 21 and the inspection tool region 120 The point is that the inspection area 100 including the inspection element such as the inspection wiring is arranged as a different block.

As shown in FIG. 10A, the semiconductor device wafer 54 is configured by arranging a plurality of pairs of one inspection area 100 and one inspection tool area 120 in a line. FIG. 10B shows one inspection area 100.
2 shows a pair of a plurality of thermoelectric power generation structures 21 formed in the inspection tool region 120, while a plurality of thermoelectric power generation structures 21 are formed in the inspection tool region 120. A plurality of elements under test 101 are formed corresponding to the electromotive force generation structure 21. Then, the corresponding components of the thermoelectromotive force generating structure 21 and the element to be inspected 101 are connected by the inspection wiring 37. Inspection element 10
For example, 1 includes two adjacent wirings to be inspected as described above.

Therefore, the semiconductor device wafer 5
4, the inspection is performed in the same procedure as in the first embodiment and the like. If a short-circuit defect exists between the two wirings included in the element 101 to be inspected, for example,
When 1 is irradiated with the laser beam, a current flows through each wiring in a path indicated by an arrow 61, and a short-circuit defect can be detected. Therefore, also in the seventh embodiment, the same effects as those in the first embodiment can be obtained.

As described in the fifth and sixth embodiments, the thermoelectromotive force generating structure 21 can be formed in the lowermost layer of the wiring. Therefore, when the free area can be set relatively freely, such as in a gate array or TEG, the inspection tool area 120 including the thermoelectromotive force generating structure 21 is previously secured and manufactured, and That is, the region having the original function as a semiconductor device may be designed according to the subsequent requirements. Therefore, in the present embodiment, in addition to the above-described effects, an effect is obtained that flexibility in designing and manufacturing the semiconductor device wafer 54 is increased. In the present embodiment, since the thermoelectromotive force generating structure 21 and the element 101 to be inspected are arranged relatively far apart, the element 10 to be inspected having a short-circuit defect is located.
In order to make it easy to discriminate 1 from each other, it is desirable that the layout be such that the correspondence between the thermoelectromotive force generating structure 21 and the element 101 to be inspected is easily understood.

That is, by using an appropriate inspection system as described above, it is possible to obtain a position recognition accuracy of about 400 nm, but it is only possible to specify with this accuracy the irradiation position of the laser beam, that is, the thermoelectromotive force generation structure. 21 position. Therefore, the element under test 101 in which the short defect actually exists is determined based on the specified thermoelectromotive force generation structure 21, and the correspondence between the thermoelectromotive force generation structure 21 and the element under test 101 can be understood. An easy layout is desirable.

More specifically, for example, as shown in FIG. 10B, the thermoelectromotive force generating structure 21 is simply changed from right to left, and the element under test 101 corresponding thereto is simply changed from left to right. If they are arranged, the correspondence between the two is clear, and the element to be inspected 101 having the short defect can be reliably specified from the thermoelectromotive force generation structure 21 specified by the magnetic field detection.
The semiconductor device wafer 5 shown in FIG.
4, the inspection tool area 1 including the thermoelectromotive force generation structure 21
20 and the inspection area 100 are arranged regularly,
It is not always necessary, depending on the availability of chips,
Needless to say, they can be freely arranged.

[Eighth Embodiment] A non-destructive inspection apparatus according to an eighth embodiment of the present invention will now be described. FIG. 11 is a configuration diagram showing a nondestructive inspection apparatus according to the eighth embodiment. In the figure, the same elements as those in FIG. 2 and the like are denoted by the same reference numerals, and a detailed description thereof will be omitted here. Nondestructive inspection device 108 shown in FIG.
Is different from the nondestructive inspection device 104 shown in FIG. 2 in that the magnetic field detector 5 is specifically SQUID (Superco
producing Quantum Interferer
ence device (superconducting quantum interference device) 55, and the addition of liquid nitrogen 9, heat insulating materials 8a and 8b, and magnetic shielding material 10 attached to SQUID 55.

In the current state of the art, to detect a weak magnetic field based on a thermoelectromotive force current, the most sensitive SQUID 55 is the most sensitive magnetic field observation method. SQUI
D can be roughly classified into a low-temperature SQUID using a low-temperature superconductor such as Nb (niobium) and a high-temperature superconducting SQUID using an oxide superconductor. Since a low-temperature SQUID that requires cooling with liquid helium is difficult to handle in terms of cost and maintenance, a high-temperature superconducting SQUID sufficient for cooling with liquid nitrogen 9 was used here. As a specific material of the high-temperature superconducting SQUID, YBCO (Y
-Ba-Cu-O) and HBCO (Ho-Ba-Cu-
O).

The liquid nitrogen 9 is for cooling the SUQID 55, and the liquid nitrogen 9 and the semiconductor device wafer 4
0 is insulated by a heat insulating material 8a, and liquid nitrogen 9
The space between the surroundings is insulated by a heat insulating material 8b. As a specific material of the heat insulating material 8a, styrene foam is preferable because it can be easily made thin and has a high heat insulating effect. Further, in order to cut off magnetic field noise mixed in from the surroundings, the entirety is covered with the magnetic shield material 10 except for the location where the laser beam 53 is incident. Forming a hole in the magnetic shield material 10 through which the laser beam 3 passes does not significantly affect the magnetic sealing effect.

As shown in FIG. 11, high-temperature superconducting SQUI
D is normally used in a state of being immersed in liquid nitrogen 9, and therefore, it is necessary to insert a heat insulating material 8a between the SQUID 55 and the semiconductor device wafer 40 to keep the semiconductor device wafer 40 at a temperature close to room temperature. Semiconductor device wafer 4
0 is a test result of how low a temperature can withstand, and a temperature that has been sufficiently proven in the past is about -55 degrees Celsius.

Actual test conditions showing this resistance include, for example, exposure to +150 degrees Celsius for 10 minutes or more, and after reaching −55 degrees Celsius within 15 minutes, 10-55 degrees Celsius.
Exposure to +150 degrees Celsius within 15 minutes, and then to +150 degrees Celsius for more than 10 minutes, ...
Is repeated ten to thousand times, and the temperature is a value obtained under such severe test conditions. Even in such a test, the chip itself shows sufficient resistance, so that it is considered that there is no problem even if the chip is exposed to a lower temperature in a short-time inspection, but there is no sufficient data showing the limit at present.

The semiconductor device wafer 40 having the configuration shown in FIG.
It is important to keep the temperature close to room temperature to prevent frost from adhering. As a result of an experiment conducted by the inventors of the present invention, it has been found that if styrofoam is used as the heat insulating material 8a, even if the thickness is reduced to about 0.3 mm, the chip can be maintained at a temperature that does not cause frost. .

In order for the SQUID 55 to operate normally, it is necessary to maintain a constant temperature within a predetermined temperature range. In the case of the configuration shown in FIG. 11, since it is immersed in the liquid nitrogen 9, it is sufficient to add the amount of the liquid nitrogen 9 appropriately so that the SQUID 55 is sufficiently immersed.

When long-term inspection is performed continuously, automatic supply is convenient. The automatic nitrogen supply device has a sufficient practical track record for use with EDX (energy dispersive X-ray analyzer) used for elemental analysis, and may be used. As described above, in the nondestructive inspection device 108 according to the eighth embodiment, since the SQUID 55 having the highest sensitivity in the current technical level is used, a weak magnetic field due to a current flowing through a short defect can be detected with a high S / N. As a result, a good magnetic field scanning image can be obtained.

[Ninth Embodiment] Next, a ninth embodiment of the present invention will be described. FIG. 12 is a configuration diagram showing a nondestructive inspection device according to a ninth embodiment. In the figure, the same elements as those in FIG. 11 are denoted by the same reference numerals, and a detailed description thereof will be omitted.
The non-destructive inspection device 110 shown in FIG. 12 differs from the non-destructive inspection device 108 in FIG. 11 in that the cooler 11 is used as a cooling method for the SQUID 55. That is,
In the non-destructive inspection apparatus 110, a cooler 11 is installed inside the magnetic shield material 10, a SQUID 55 is placed on the cooler 11 in contact with the cooler 11, and a semiconductor device wafer 40 is further placed thereon. Cooler 11 and SQUI
By bringing the SQUID 55 into contact with the ID 55, the SQUID 55 can be easily cooled to the liquid nitrogen temperature (77K) or lower.

In the present embodiment, the opening formed in the magnetic shield material 10 for guiding the laser beam 53 is closed by the transparent glass material 13, and the inside of the magnetic shield material 10 becomes airtight. I have. Then, a vacuum pump 12 communicating with the inside of the magnetic shield member 10 is provided to evacuate the inside of the magnetic shield member 10 to prevent heat dissipation.

Cooling the SQUID 55 by the cooler 11 and evacuating the inside at the same time has the following three advantages. The first advantage is that there is no need to supply liquid nitrogen 9 and maintenance is easy. Of course, this is the case where the liquid nitrogen 9 is not used as the cooler 11, and if the cooling function depends on the liquid nitrogen 9, this advantage cannot be enjoyed.

The second advantage is that the semiconductor device wafer 40
And SQUID 55 can be reduced in distance. Generally, the magnetic field caused by the thermoelectromotive force is larger as the distance from the current path is shorter. Therefore, the shorter the distance between the semiconductor device wafer 40 and the SQUID 55, the more the magnetic field can be detected in a strong place, and the higher the detection sensitivity. Liquid nitrogen 9
In the case where the semiconductor device is cooled by dipping in liquid nitrogen, as shown in FIG.
And the heat insulating material 8a intervene. On the other hand, when cooling with the cooler 11, as can be seen from FIG. 12, there is only a slight gap between the semiconductor device wafer 40 and the SQUID 55, and both can be brought extremely close.

The third advantage is that the semiconductor device wafer 40
There is no need to worry about frost on it. Therefore, the possibility of deterioration of the semiconductor device wafer 40 due to frost is eliminated. 12, the semiconductor device wafer 40 is irradiated with the laser beam 53 through the glass material 13.
The selection should be made with emphasis on the transmittance at the wavelength of 0 nm.
The transmittance at a wavelength of 633 nm may not be very good.

The reason is that a large power laser beam is required to generate a sufficient thermoelectromotive current, but not so large power is required to obtain a scanning laser microscope image. It is. In any case, the cost may be ultimately determined by a trade-off between the cost of the laser generator 51 and the light receiving element and the detection sensitivity.

[0101]

As described above, the present invention is directed to a semiconductor device including first and second conductors disposed close to a semiconductor substrate, wherein the semiconductor device includes a heat conductive member disposed on the semiconductor substrate. An electromotive force generator, a first wiring connecting one end of the thermoelectromotive force generator to the first conductor, and connecting the other end of the thermoelectromotive generator to the second conductor. And a second wiring to be formed. Further, the present invention is a method of manufacturing a semiconductor device including first and second conductors disposed close to each other on a semiconductor substrate, wherein a thermoelectric generator is disposed on the semiconductor substrate. Connecting one end of the thermoelectromotive force generator to the first conductor by a first wiring, and connecting the other end of the thermoelectromotive force generator to the second conductor by a second wiring. It is characterized by doing.

The present invention also includes a thermoelectric generator including first and second conductors disposed close to each other on a semiconductor substrate, wherein the thermoelectric generator is disposed on the semiconductor substrate; A semiconductor device including a first wire connecting one end of a generator and the first conductor, and a second wire connecting the other end of the thermoelectric generator and the second conductor. A non-destructive inspection method, irradiating the thermoelectromotive force generator with laser light, detecting the magnetic field generated when irradiating the laser light on the thermoelectromotive force generator, the detection result of the magnetic field Based on this, it is characterized in that the presence or absence of a short-circuit defect relating to the first and second conductors is determined.

The present invention also provides a thermo-electromotive force generator including first and second conductors disposed close to a semiconductor substrate, wherein the thermo-electromotive force generator is disposed on the semiconductor substrate. A semiconductor device including a first wiring connecting one end of a generator and the first conductor, and a second wiring connecting the other end of the thermoelectric generator and the second conductor. A non-destructive inspection device, a laser light irradiating means for irradiating the thermoelectromotive force generator with laser light, and a magnetic field detection for detecting a magnetic field generated when the thermoelectromotive force generator is irradiated with the laser light Means.

In the present invention, when a short-circuit defect exists between the first and second conductors, a thermo-electromotive force generating structure is generated when the thermo-electromotive force generating structure formed on the semiconductor substrate is irradiated with laser light. A current flows through the first and second conductors and the first and second wirings due to the thermoelectromotive force, and a magnetic field is generated. Therefore, by detecting this magnetic field with a magnetic field detecting means such as SQUID, the presence of a short defect can be detected. As described above, according to the present invention, it is possible to detect a short-circuit defect, which is impossible with the conventional inspection technology based on thermoelectromotive force. Moreover,
Inspection can be performed on a semiconductor substrate constituting a semiconductor device in a non-contact manner, so that inspection can be performed even at a manufacturing stage before bonding pads are formed on the semiconductor substrate. As a result, an electrical short can be detected at an early stage in the manufacturing process of a semiconductor device, and appropriate and prompt measures can be taken, thereby greatly improving product yield and reliability. .

[Brief description of the drawings]

FIG. 1A is a configuration diagram illustrating an example of a nondestructive inspection apparatus according to the present invention, and FIG. 1B is a partially enlarged cross section illustrating a portion to be inspected in an example of a semiconductor wafer including chips constituting a semiconductor device according to the present invention; It is a side view.

FIG. 2 is a configuration diagram illustrating a nondestructive inspection device according to a second embodiment of the present invention.

FIG. 3A is a partially enlarged cross-sectional side view showing a portion to be inspected in an example of a semiconductor wafer including a chip constituting a non-destructive inspection semiconductor device according to a second embodiment;
(B) is a partial enlarged plan view of the same.

FIG. 4A is a partially enlarged sectional side view showing a semiconductor wafer including a chip constituting a nondestructive inspection semiconductor device according to a third embodiment, and FIG. 4B is a partially enlarged plan view of the same.

FIG. 5A is a partially enlarged cross-sectional side view showing a semiconductor wafer including a chip constituting a nondestructive inspection semiconductor device according to a fourth embodiment, and FIG. 5B is a partially enlarged plan view of the same.

FIG. 6A is a partially enlarged cross-sectional side view showing a semiconductor wafer including a chip constituting a nondestructive inspection semiconductor device according to a fifth embodiment, and FIG. 6B is a partially enlarged plan view of the same.

FIG. 7A is a partially enlarged sectional side view showing a semiconductor wafer including a chip constituting a non-destructive inspection semiconductor device according to a sixth embodiment, and FIG. 7B is a partially enlarged plan view of the same.

8A is a partially enlarged cross-sectional side view showing a state where inspection wiring is deleted from the wafer shown in FIG. 7A, and FIG. 8B is a partially enlarged plan view thereof.

9A is a partially enlarged cross-sectional side view showing a path of a current flowing at the time of inspection on the wafer shown in FIG. 7A, and FIG. 9B is a partially enlarged plan view thereof.

FIG. 10A is a conceptual diagram showing, as a block, a layout on a semiconductor wafer including chips constituting the semiconductor device of the seventh embodiment, and FIG. 10B is repeated in FIG. It is the conceptual diagram which took out the block and showed the internal structure and the mutual connection relationship.

FIG. 11 is a configuration diagram illustrating a nondestructive inspection device according to an eighth embodiment.

FIG. 12 is a configuration diagram showing a nondestructive inspection device according to a ninth embodiment.

FIG. 13 is a configuration diagram illustrating an example of a conventional nondestructive inspection apparatus.

FIG. 14 is a configuration diagram illustrating an example of a conventional nondestructive inspection apparatus.

[Explanation of symbols]

1 ... Laser generator, 2 ... Optical system, 3 ... Laser beam, 4 ... Semiconductor device chip or wafer, 5 ...
Magnetic field detector, 6: Control / image processing system, 7: Image display device, 8a, 8b ... Heat insulation material, 9: Liquid nitrogen, 10 ...
Magnetic shield material, 11 Cooler, 12 Vacuum pump, 13 Glass material, 14 Bonding pad,
Reference numeral 20: wiring for forming a thermo-electromotive force generating structure, 21: a thermo-electromotive force generating structure, 31: a silicon substrate portion, 32: an insulating layer, 33: a contact portion, 34a, 34b ... a first wiring, 35a, 35b ... via, 35b ... via, 40
…… Semiconductor device wafer, 42 …… Short defect, 4
4 semiconductor device wafer, 46 semiconductor device wafer, 48 semiconductor device wafer, 50 semiconductor device wafer, 52 semiconductor device wafer, 5
3 ... laser beam, 54 ... semiconductor device wafer,
55 SQUID, 61 Current path, 100 Area to be inspected, 101 Element to be inspected, 102 Non-destructive inspection apparatus, 104 Non-destructive inspection apparatus, 106 Control
Image processing system, 108 non-destructive inspection device, 110 non-destructive inspection device, 115 prober, 120 inspection tool region, 131 current change detector, 305 inspection via.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G053 AA11 AB01 AB14 BA16 CA10 DB07 DB19 2G060 AA09 AA20 AE01 AF01 AF13 EA03 EA04 EA06 EA07 EB09 HC10 HC18 KA16 4M106 AA01 BA05 CA16 CA28 DH01 DH11 DJ23 4M113 AC06 AC46

Claims (56)

[Claims] A first substrate disposed in close proximity on a semiconductor substrate;
A thermoelectric generator disposed on the semiconductor substrate; and a second connecting the one end of the thermoelectric generator to the first conductor. 1. A non-destructive inspection semiconductor device, comprising: a first wiring; and a second wiring connecting the other end of the thermoelectric generator and the second conductor. 2. The non-destructive inspection semiconductor device according to claim 1, wherein said thermoelectromotive force generator is arranged close to said first and second conductors. 3. The thermoelectric generator and the first and second wirings are integrally formed of the same material, and the location of the thermoelectric generator is different from the first and second wirings. 2. The non-destructive inspection semiconductor device according to claim 1, wherein the semiconductor device is formed to have a width smaller than that of the portion. 4. The non-destructive inspection semiconductor device according to claim 3, wherein said material is titanium silicide. 5. The non-destructive inspection semiconductor device according to claim 1, wherein said first and second conductors are wiring. 6. The first and second conductors are extended on the semiconductor substrate via an insulating layer, and an insulating layer is further formed on the first and second conductors. The electromotive force generator and the first and second wires are connected to the first
2. The non-destructive inspection semiconductor device according to claim 1, wherein the semiconductor device is formed on an insulating layer on the second conductor. 7. The first and second conductors and the first and second conductors.
7. The non-destructive inspection semiconductor device according to claim 6, wherein the second wiring is connected to the second wiring by a via penetrating the insulating layer. 8. The non-destructive inspection semiconductor device according to claim 1, wherein said first and second conductors extend substantially in a straight line with one end thereof approaching each other. 9. At least one of the first and second conductors and at least one of the first and second wirings extend substantially in parallel, and extend substantially in parallel. 2. The non-destructive inspection semiconductor device according to claim 1, wherein the conductor and the wiring have different widths. 10. The first and second conductors are juxtaposed, and the first and second wirings and the thermoelectric generator are arranged in a direction in which the first and second conductors extend. 2. The non-destructive inspection semiconductor device according to claim 1, wherein the semiconductor device extends in a direction intersecting with the semiconductor device. 11. The first conductor and the first wiring,
2. The non-destructive inspection semiconductor device according to claim 1, wherein the via connecting the second conductor and the second wiring is an inspection via. 12. The non-destructive inspection semiconductor device according to claim 1, wherein the thermoelectric generator is disposed in a layer closer to the semiconductor substrate than the first and second conductors. . 13. The non-destructive inspection semiconductor device according to claim 1, wherein at least one of said first and second wirings comprises a plurality of wirings formed in mutually different layers. 14. The non-conductive device according to claim 1, wherein at least one of said first and second wirings is formed integrally with one of said first and second conductors. Semiconductor device for destructive inspection. 15. The thermo-electromotive force generator is located at a position where laser light incident from the back side of the semiconductor substrate reaches the thermo-electromotive force generator without being blocked by a structure. The non-destructive inspection semiconductor device according to claim 1. 16. The non-destructive inspection semiconductor device according to claim 15, wherein said structure is a wiring. 17. A thermoelectric generator including a plurality of thermoelectric generators and a plurality of pairs of the first and second conductors, each thermoelectric generator being connected to the thermoelectric generator. 2. The non-destructive inspection semiconductor device according to claim 1, wherein the semiconductor device is arranged at a position corresponding to a pair of the first and second conductors. 18. A thermoelectric generator and a plurality of pairs of the first and second conductors are both arranged substantially in a line, and each thermoelectric generator is in the same or opposite order. 2. The non-destructive inspection semiconductor device according to claim 1, wherein the semiconductor device is connected to a pair of the first and second conductors. 19. A method of manufacturing a semiconductor device including first and second conductors disposed close to each other on a semiconductor substrate, comprising: disposing a thermoelectric generator on the semiconductor substrate; A first end of the thermoelectric generator and the first conductor
The other end of the thermoelectromotive force generator and the second conductor
A method for manufacturing a non-destructive inspection semiconductor device, characterized in that the semiconductor device is connected by the above-mentioned wiring. 20. The method according to claim 19, wherein the thermoelectric generator is arranged close to the first and second conductors. 21. The thermoelectric generator and the first and second wirings are integrally formed of the same material, and the location of the thermoelectric generator is different from that of the first and second wirings. 20. The method according to claim 19, wherein the width is formed to be narrower than the location.
A method for manufacturing a semiconductor device for nondestructive inspection according to the above. 22. The method according to claim 21, wherein titanium silicide is used as the material. 23. The method according to claim 19, wherein the first and second conductors are wirings. 24. The first and second conductors extend on the semiconductor substrate via an insulating layer, and further form an insulating layer on the first and second conductors, 20. The semiconductor device for nondestructive inspection according to claim 19, wherein the electromotive force generator and the first and second wirings are formed on an insulating layer on the first and second conductors. Method. 25. The non-destructive inspection semiconductor device according to claim 24, wherein the first and second conductors are connected to the first and second wirings by vias penetrating an insulating layer. Manufacturing method. 26. The method of manufacturing a non-destructive inspection semiconductor device according to claim 19, wherein the first and second conductors extend substantially linearly with one end thereof approaching each other. . 27. At least one of the first and second conductors and at least one of the first and second wirings extend substantially in parallel, and extend substantially in parallel. 20. The method of manufacturing a non-destructive inspection semiconductor device according to claim 19, wherein the conductor and the wiring are formed to have different widths. 28. The first and second conductors are juxtaposed, and the first and second wirings and the thermoelectric generator are arranged in a direction in which the first and second conductors extend. 20. The method for manufacturing a non-destructive inspection semiconductor device according to claim 19, wherein the semiconductor device is extended in an intersecting direction. 29. The first conductor and the first wiring,
20. The method of manufacturing a non-destructive inspection semiconductor device according to claim 19, wherein the via connecting the second conductor and the second wiring is formed as an inspection via. 30. The non-destructive inspection semiconductor device according to claim 19, wherein the thermoelectric generator is disposed in a layer closer to the semiconductor substrate than the first and second conductors. Method. 31. The method of claim 19, wherein at least one of the first and second wirings comprises a plurality of wirings formed in different layers. Method. 32. The nondestructive inspection according to claim 19, wherein at least one of the first and second wirings is formed integrally with one of the first and second conductors. Of manufacturing semiconductor devices for electronic devices. 33. The thermo-electromotive force generator is arranged at a position where laser light incident from the back surface side of the semiconductor substrate reaches the thermo-electromotive force generator without being blocked by a structure. A method for manufacturing a semiconductor device for nondestructive inspection according to claim 19. 34. The method according to claim 33, wherein the structure is a wiring. 35. A plurality of said thermoelectromotive force generators, and a plurality of pairs of said first and second conductors, each of said thermoelectromotive force generators being connected to said thermoelectric power generator connected to said thermoelectric generator. 2. The method for manufacturing a non-destructive inspection semiconductor device according to claim 1, wherein the semiconductor device is arranged at a position corresponding to a pair of the first and second conductors. 36. A plurality of said thermoelectric generators and a plurality of pairs of said first and second conductors are both arranged substantially in a line, and each thermoelectric generator is of the same or opposite order. 2. The method of manufacturing a non-destructive inspection semiconductor device according to claim 1, wherein the semiconductor device is connected to a pair of the first and second conductors. 37. A thermoelectric generator including first and second conductors disposed close to each other on a semiconductor substrate, the thermoelectric generator being disposed on the semiconductor substrate, and one end of the thermoelectric generator. Non-destructive inspection of a semiconductor device including: a first wiring connecting the first conductor to the first conductor; and a second wiring connecting the other end of the thermoelectric generator to the second conductor. Irradiating the thermoelectromotive force generator with laser light, detecting a magnetic field generated when irradiating the thermoelectric power generator with the laser light, and detecting the magnetic field based on a detection result of the magnetic field. A non-destructive inspection method characterized by determining the presence or absence of a short defect relating to the first and second conductors. 38. The nondestructive inspection method according to claim 37, wherein the laser beam converged as the laser beam is applied to the thermoelectric generator. 39. An irradiation position of the laser beam on the semiconductor substrate is moved, an irradiation position of the laser beam on the semiconductor substrate is associated with a position on a screen of a display device, and the intensity of the detected magnetic field is detected. 39. The non-destructive inspection method according to claim 38, wherein a scanning magnetic field image is generated by displaying the scanning magnetic field on the display device in association with brightness or color. 40. The nondestructive inspection method according to claim 39, wherein the laser beam is moved while fixing the semiconductor substrate. 41. The nondestructive inspection method according to claim 39, wherein the semiconductor substrate is moved while fixing the laser beam. 42. A scanning laser microscope image of the semiconductor substrate is acquired, and an image obtained by superimposing the scanning magnetic field image and the scanning laser microscope image on a screen of the display device is displayed. Nondestructive inspection method described. 43. An OBI penetrating the semiconductor substrate,
The nondestructive inspection method according to claim 38, wherein the semiconductor substrate is irradiated with the laser beam having a wavelength that does not generate a C current. 44. The non-destructive inspection method according to claim 43, wherein said semiconductor substrate is a silicon substrate. 45. The nondestructive inspection method according to claim 37, wherein the laser beam is irradiated from the back side of the semiconductor substrate, and the magnetic field is detected on the front side of the semiconductor substrate. 46. The nondestructive inspection method according to claim 37, wherein the magnetic field is detected by SQUID. 47. A thermoelectric generator including first and second conductors disposed close to a semiconductor substrate, the thermoelectric generator being disposed on the semiconductor substrate, and one end of the thermoelectric generator. Non-destructive inspection of a semiconductor device including: a first wiring connecting the first conductor to the first conductor; and a second wiring connecting the other end of the thermoelectric generator to the second conductor. A laser light irradiating means for irradiating the thermoelectromotive force generator with laser light, and a magnetic field detecting means for detecting a magnetic field generated when the thermoelectromotive force generator is irradiated with the laser light. Non-destructive inspection equipment characterized by the above-mentioned. 48. The nondestructive inspection apparatus according to claim 47, wherein said laser light irradiation means irradiates said converged laser beam to said thermoelectromotive force generator. 49. A scanning unit for moving an irradiation position of the laser beam on the semiconductor substrate, and associating the irradiation position of the laser beam on the semiconductor substrate with a position on a screen of a display device and detecting the position. 49. The nondestructive inspection apparatus according to claim 48, further comprising: an image generating unit that displays the intensity of the magnetic field on the display device in association with the brightness or the color to generate a scanning magnetic field image. 50. The nondestructive inspection apparatus according to claim 49, wherein said scanning means moves said laser beam while fixing said semiconductor substrate. 51. The nondestructive inspection apparatus according to claim 49, wherein said scanning means moves said semiconductor substrate while fixing said laser beam. 52. The image generating means acquires a scanning laser microscope image of the semiconductor substrate, and displays an image obtained by superimposing the scanning magnetic field image and the scanning laser microscope image on a screen of the display device. 50. The non-destructive inspection device according to claim 49, wherein: 53. The non-destructive inspection according to claim 48, wherein the laser beam irradiation means irradiates the semiconductor substrate with the laser beam having a wavelength that does not generate an OBIC current while transmitting through the semiconductor substrate. apparatus. 54. The non-destructive inspection device according to claim 53, wherein the semiconductor substrate is a silicon substrate. 55. The laser beam irradiation means irradiates the laser light from the back side of the semiconductor substrate, and the magnetic field detection means detects the magnetic field on the front side of the semiconductor substrate. Item 48. The nondestructive inspection device according to Item 47. 56. The nondestructive inspection apparatus according to claim 47, wherein said magnetic field detection means includes a SQUID.