Analysis device and analysis method

Abstract

This analysis device 1 comprises: a tester 10 that inputs a test signal St having a prescribed frequency to a semiconductor device D; an X-ray irradiation device 11 that irradiates the semiconductor device D with X-rays R; a detector 15 that detects X-rays (transmitted X-rays Rt) from the semiconductor device D due to the irradiation with the X-rays R and outputs a detection signal Sd on the basis of the detected result; and a signal processing device 16 that performs, on the detection signal Sd, signal processing based on the prescribed frequency.

Description

Analysis Device and Analysis Method

[0001] The present disclosure relates to an analysis device and an analysis method.

[0002] Currently, in the failure analysis of semiconductor devices, luminescence analysis for detecting light generated inside the device, or OBIRCH (Optical Beam Induced Resistance Change) analysis for irradiating the inside of the device with laser light, etc. are the mainstream. However, in the most advanced semiconductor devices, the wiring layers on both sides of the silicon substrate are multilayered, and with conventional methods, it has become difficult to detect signals from the semiconductor device to be analyzed.

[0003] In response to such a situation, in recent years, OBIRCH analysis using X-rays instead of near-infrared light has been proposed. For example, the analysis device described in Patent Document 1 includes a stage on which a semiconductor device is placed, a power supply for supplying a voltage to the semiconductor device, an X-ray source for irradiating the semiconductor device with X-rays, and a current meter for detecting the value of the current flowing through the semiconductor device.

[0004] Japanese Patent Application Laid-Open No. 2001-160573

[0005] When using X-rays, even if the wiring layer of the semiconductor device is multilayered, it is considered possible to deeply observe the inside of the semiconductor device. On the other hand, the response of the semiconductor device to X-rays is weak, and improving the signal-to-noise ratio of the signal used for analysis has become an issue.

[0006] The present disclosure has been made to solve the above problems, and an object thereof is to provide an analysis device and an analysis method capable of accurately performing failure analysis on a semiconductor device with a multilayered wiring layer.

[0007] The gist of the present disclosure is as follows.

[0008] [1] An analysis device comprising: a tester that inputs a test signal having a predetermined frequency to a semiconductor device; an X-ray irradiation device that irradiates the semiconductor device with X-rays; a detector that detects X-rays from the semiconductor device due to the X-ray irradiation and outputs a detection signal based on the detection result; and a signal processing device that performs signal processing on the detection signal based on the predetermined frequency.

[0009] This analysis device can capture periodic structural changes within semiconductor devices caused by heat generated by the input test signal as changes in X-rays emitted from the semiconductor device. By using X-rays, it is possible to observe the interior of semiconductor devices in depth, even if the wiring layers of the semiconductor device are multilayered. Furthermore, this analysis device processes the detection signal based on a predetermined frequency used for the test signal. As a result, even if the response of the semiconductor device to X-rays is weak, the signal-to-noise ratio of the signal used for analysis is improved.

[0010] [2] The signal processing device is the analysis device according to [1], which extracts a component corresponding to the predetermined frequency from the detection signal. In this case, by extracting a component corresponding to the predetermined frequency used in the test signal from the detection signal, the signal-to-noise ratio of the signal used for analysis can be improved more reliably.

[0011] [3] The analysis apparatus according to [1] or [2], wherein the detector detects at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays from the semiconductor device due to X-ray irradiation. In this case, periodic structural changes within the semiconductor device due to heat etc. generated by the input of a test signal can be captured as changes in at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays. By detecting at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays, failure analysis of the semiconductor device can be performed with high accuracy.

[0012] [4] The detector is a two-dimensional X-ray detector, and the analysis apparatus according to any one of [1] to [3] outputs an X-ray image based on X-rays from the semiconductor device as the detection signal. In this case, failure analysis of the semiconductor device can be performed with high accuracy by analyzing the X-ray image.

[0013] [5] The signal processing device weights the time-series images included in each frame of the X-ray image based on the predetermined frequency, and generates a lock-in image by integrating the images at the same timing in the time-series images of each frame after weighting, as described in [4]. In this case, periodic structural changes within the semiconductor device can be emphasized in the generated lock-in image. Therefore, failure analysis of the semiconductor device can be performed with high accuracy.

[0014] [6] The analysis apparatus according to [4] or [5], wherein the signal processing device sets a predetermined analysis area in the X-ray image and generates a mapping image relating the brightness values ​​of the X-ray image in the analysis area to the irradiation position of the X-rays on the semiconductor device. In this case, for example, brightness information of interference spots associated with changes in the crystal lattice spacing of Si used in the substrate of the semiconductor device can be imaged and captured. Therefore, minute structural changes in the Si crystal lattice can be observed with high accuracy.

[0015] [7] An analysis method comprising: an input step of inputting a test signal having a predetermined frequency to a semiconductor device; an X-ray irradiation step of irradiating the semiconductor device with X-rays; a detection step of detecting X-rays from the semiconductor device due to the X-ray irradiation and outputting a detection signal based on the detection result; and a signal processing step of performing signal processing on the detection signal based on the predetermined frequency.

[0016] This analysis method allows for the detection of periodic structural changes within a semiconductor device caused by heat generated by the input test signal, as changes in X-rays emitted from the semiconductor device. Using X-rays makes it possible to deeply observe the interior of a semiconductor device, even if its wiring layers are multi-layered. Furthermore, this analysis method performs signal processing of the detection signal based on a predetermined frequency used in the test signal. This improves the signal-to-noise ratio (SNR) of the signal used for analysis, even if the semiconductor device's response to X-rays is weak.

[0017] [8] The analysis method according to [7], wherein the signal processing step involves extracting a component corresponding to the predetermined frequency from the detection signal. In this case, by extracting a component corresponding to the predetermined frequency used in the test signal from the detection signal, the signal-to-noise ratio of the signal used for analysis can be improved more reliably.

[0018] [9] The analysis method according to [7] or [8], wherein the detection step involves detecting at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays from the semiconductor device due to X-ray irradiation. In this case, periodic structural changes within the semiconductor device due to heat generated by the input of a test signal can be captured as changes in at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays. By detecting at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays, failure analysis of the semiconductor device can be performed with high accuracy.

[0019]

[10] The analysis method according to any one of [7] to [9], wherein the detection step outputs an X-ray image based on X-rays from the semiconductor device as the detection signal. In this case, failure analysis of the semiconductor device can be performed with high accuracy by analyzing the X-ray image.

[0020]

[11] The analysis method according to

[10] , wherein the signal processing step involves weighting the time-series images included in each frame of the X-ray image based on the predetermined frequency, and integrating the images at the same timing in the time-series images of each frame after weighting to generate a lock-in image. In this case, periodic structural changes within the semiconductor device can be emphasized in the generated lock-in image. Therefore, failure analysis of the semiconductor device can be performed with high accuracy.

[0021]

[12] The analysis method according to

[10] or

[11] , wherein the signal processing step includes setting a predetermined analysis area in the X-ray image and generating a mapping image in which the brightness values ​​of the X-ray image in the analysis area are associated with the irradiation position of the X-rays on the semiconductor device. In this case, for example, brightness information of interference spots associated with changes in the crystal lattice spacing of Si used in the substrate of the semiconductor device can be imaged and captured. Therefore, minute structural changes in the Si crystal lattice can be observed with high accuracy.

[0022] According to this disclosure, failure analysis can be performed accurately even on semiconductor devices with multiple wiring layers.

[0023] This is a block diagram showing an analysis apparatus according to one embodiment of the present disclosure. (a) is a schematic side view of a first capillary lens, and (b) is a schematic side view of a second capillary lens. This is a schematic diagram showing the process of generating a lock-in image. (a) is a diagram showing the interference spots associated with the change in the crystal lattice spacing of Si due to heat, (b) is a diagram showing an example of a lock-in image in a normal semiconductor device, and (c) is a diagram showing an example of a lock-in image in an abnormal semiconductor device. (a) is a diagram showing an example of setting the analysis area, and (b) is a diagram showing an example of a mapping image. This is a flowchart showing an analysis method according to one embodiment of the present disclosure.

[0024] Hereinafter, with reference to the drawings, preferred embodiments of the analysis apparatus and analysis method relating to one aspect of this disclosure will be described in detail.

[0025] Figure 1 is a block diagram showing an analysis apparatus according to one embodiment of the present disclosure. The analysis apparatus 1 shown in Figure 1 is an apparatus that uses X-rays R to analyze the cause of failure, the factors contributing to the cause of failure, and the location of failure in a semiconductor device D, or to narrow down the location of failure. The analysis apparatus 1 analyzes the periodic structural changes of the semiconductor device D caused by heat or mechanical movement generated by the input of a test signal St using X-ray lock-in imaging, and identifies the cause of failure of the semiconductor device D, etc.

[0026] Examples of semiconductor devices D to be analyzed include discrete semiconductor elements, optoelectronic elements, sensors / actuators, logic LSIs (Large Scale Integrations), memory elements, linear ICs (Integrated Circuits), or hybrid devices thereof. Examples of discrete semiconductor elements include diodes and power transistors. Logic LSIs may consist of MOS (Metal-Oxide-Semiconductor) transistors, bipolar transistors, etc. Semiconductor device D may also be a package containing semiconductor devices, a composite substrate, etc. Semiconductor device D may have metal layers formed on both sides of the substrate, or a three-dimensional structure in which multiple semiconductor devices are stacked. Semiconductor device D may have a substrate and a metal layer formed on the substrate. For example, a silicon substrate is used as the substrate.

[0027] As shown in Figure 1, the analysis device 1 comprises a tester 10, an X-ray irradiation device 11, a focusing optical system 12, a stage 14, a detector 15, a signal processing device 16, and a computer 17.

[0028] The tester 10 is a device that inputs a test signal St having a predetermined frequency F to a semiconductor device D. The test signal St is a drive signal for the semiconductor device D, and upon receiving the test signal St, the semiconductor device D is driven at the predetermined frequency F. The semiconductor device D periodically generates heat based on the predetermined frequency F, and periodic structural changes (such as expansion) may occur based on this heat. In semiconductor devices D having a MEMS (Micro Electro Mechanical Systems) mechanism or a NEMS (Nano Electro Mechanical System) mechanism, periodic motion occurs based on a second frequency F2, and periodic structural changes may occur due to this periodic motion. The tester 10 also outputs the test signal St used to drive the semiconductor device D to the signal processing device 16.

[0029] The X-ray irradiation device 11 is a device that irradiates a semiconductor device D with X-rays R. The X-ray irradiation device 11 has an X-ray source that emits X-rays R. Any radiation source capable of emitting X-rays can be used as the X-ray source. The radiation source may also be a gamma-ray source.

[0030] The focusing optical system 12 is an optical system that focuses the X-rays R output from the X-ray irradiation device 11 to an arbitrary position on the semiconductor device D. The focusing optical system 12 is composed of, for example, a capillary lens. A capillary lens is a glass block in which a plurality of fine holes are provided parallel to each other. Under conditions where the frequency of the X-rays R is higher than the plasma frequency given by the electron density inside the capillary lens, the refractive index of the X-rays R becomes less than 1 inside the glass. As a result, X-rays incident on one end of the hole in the capillary lens undergo total internal reflection when they are shallowly incident on the glass surface and are guided to the other end of the hole.

[0031] In this embodiment, the focusing optical system 12 includes a first capillary lens 18A (see Figure 2(a)) and a second capillary lens 18B (see Figure 2(b)). The first capillary lens 18A is positioned on the X-ray irradiation device 11 side in the optical path of the X-ray R, and the second capillary lens 18B is positioned on the semiconductor device D side in the optical path of the X-ray R. Note that the focusing optical system 12 does not necessarily have to be composed of a pair of capillary lenses; it may also be configured to use a single capillary lens to direct the X-ray R emitted from the X-ray irradiation device 11 toward the focus point P on the semiconductor device D.

[0032] The first capillary lens 18A and the second capillary lens 18B both have a circular cross-section. As shown in Figure 2(a), the first capillary lens 18A gradually increases in diameter from the incident end face 18Aa to the exit end face 18Ab, with the half portion on the exit end face 18Ab side having a constant diameter. As shown in Figure 2(b), the second capillary lens 18B gradually decreases in diameter from the incident end face 18Ba to the exit end face 18Bb, with the half portion on the incident end face 18Ba side having a constant diameter.

[0033] As shown in Figure 2(a), X-rays R incident on the incident end face 18Aa of the first capillary lens 18A from the X-ray irradiation device 11 (shown as a point light source in Figure 2(a)) are emitted from the exit end face 18Ab of the first capillary lens 18A in a parallel light state. As shown in Figure 2(b), X-rays R incident on the incident end face 18Baa of the second capillary lens 18B from the exit end face 18Ab of the first capillary lens 18A in a parallel light state are emitted from the exit end face 18Bb of the second capillary lens 18B toward the focus point P on the semiconductor device D. The X-rays R emitted from the second capillary lens 18B may be incident perpendicular to the surface of the semiconductor device D, or they may be incident at a predetermined inclination angle.

[0034] Stage 14 is composed of, for example, a triaxial stage. The semiconductor device D to be analyzed is placed on Stage 14. Stage 14 moves the semiconductor device D in an in-plane direction perpendicular to the optical axis of the X-ray R from the exit end face 18Bb of the second capillary lens 18B. In this case, the first capillary lens 18A and the second capillary lens 18B may be realized with a single capillary lens. As a result, the focus point P of the X-ray R moves relative to the surface of the semiconductor device D. Alternatively, instead of configuring Stage 14 on which the semiconductor device D is placed as a movable stage, lens drive units may be attached to the first capillary lens 18A and the second capillary lens 18B as described above, and the first capillary lens 18A and the second capillary lens 18B may be moved in an in-plane direction perpendicular to the optical axis of the X-ray R from the exit end face 18Bb of the second capillary lens 18B.

[0035] Detector 15 is a device that detects X-rays R from a semiconductor device D due to irradiation with X-rays R and outputs a detection signal Sd based on the detection result. Detector 15 is an X-ray detector that detects at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays from a semiconductor device D due to irradiation with X-rays R. Here, detector 15 is composed of, for example, a flat panel X-ray detector (two-dimensional X-ray detector) or an X-ray single-point detector, and detects transmitted X-rays Rt from the semiconductor device D. Detector 15 outputs a detection signal Sd indicating the detection result to a signal processing device 16.

[0036] The signal processing device 16 is a device that performs signal processing on the detected signal Sd based on a predetermined frequency F. The signal processing device 16 extracts a component corresponding to the predetermined frequency F from the detected signal Sd and outputs an output signal Sk indicating the extracted component to the computer 17.

[0037] When the detector 15 is composed of an X-ray single-point detector, a lock-in amplifier can be used as the signal processing device 16. The lock-in amplifier may be either a digital lock-in amplifier or an analog lock-in amplifier. In this case, the signal processing device 16 superimposes a sinusoidal reference signal (here, a test signal St input from the tester 10) onto the detection signal Sd, and processes the superimposed signal with a low-pass filter to extract a component corresponding to a predetermined frequency F from the detection signal Sd. An example of a component extracted from the detection signal Sd is the amplitude of the detection signal Sd.

[0038] When the detector 15 is composed of a flat panel X-ray detector, the signal processing device 16 can be, for example, a computer. Examples of computers include personal computers, cloud servers, and smart devices (smartphones, tablet terminals, etc.). In this case, the signal processing device 16 outputs an X-ray image G0 based on X-rays R (transmitted X-rays Rt) from the semiconductor device D as a detection signal Sd. The signal processing device 16 weights the time-series images G1 contained in each frame of the X-ray image G0 based on a predetermined frequency F, and generates a lock-in image by integrating the images at the same timing in the time-series images G1 of each frame after weighting.

[0039] In the example shown in Figure 3, one period (= 1 / F) of a test signal St having a predetermined frequency F is defined as one frame, and the detector 15 acquires a time-series image G1 containing eight images G2 acquired at different timings in each frame. The signal processing device 16 superimposes a sine wave having a period corresponding to the predetermined frequency F (i.e., the period of the test signal St) onto the time-series image G1 contained in each frame, thereby weighting the time-series image G1 of each frame. Next, the signal processing device 16 integrates the first to eighth images G2 of the weighted time-series image G1 in each frame. Then, the signal processing device 16 combines the first to eighth images G2 after integration in chronological order to generate a lock-in image G3.

[0040] Furthermore, the signal processing device 16 may set a predetermined analysis area K in the X-ray image G0 and generate a mapping image G4 that associates the brightness values ​​of the X-ray image G0 in the analysis area K with the irradiation position of the X-ray R on the semiconductor device D. Such signal processing can be applied, for example, to observing changes in the crystal lattice spacing of Si used in the substrate of the semiconductor device D.

[0041] If an abnormality exists in the Si substrate within semiconductor device D to which the test signal St is input, a periodic temperature change occurs at the abnormality, as shown in Figure 4(a), causing a periodic change in the Si crystal lattice spacing. Consequently, interference spots (Bragg points) that appear in the time-series image G1 included in the X-ray image G0 are periodically displaced according to the Si crystal lattice. In the example in Figure 4(a), a central interference spot 21A and four symmetrical interference spots 21B surrounding it are shown. The spacing between interference spots 21A and 21B is a parameter corresponding to the Si crystal lattice spacing. When a temperature change occurs at the abnormality, the central interference spot 21A does not displace, but the four surrounding interference spots 21B are displaced radially around interference spot 21A.

[0042] In a normal semiconductor device D, no change in the Si crystal lattice spacing occurs in response to the input test signal St. Therefore, as shown in Figure 4(b), nothing special appears in the lock-in image G3 generated from the X-ray image G0 acquired for a normal semiconductor device D. On the other hand, in an abnormal semiconductor device D, a change in the Si crystal lattice spacing may occur in response to the input test signal St. Therefore, as shown in Figure 4(c), displacement spots 21C corresponding to the displacements of the four interference spots 21B appear in the lock-in image G3 generated from the X-ray image G0 acquired for an abnormal semiconductor device D. In Figure 4(c), the white portion of the displacement spot 21C represents the displacement of the interference spot 21B in the same phase, and the black portion of the displacement spot 21C represents the displacement of the interference spot 21B in the opposite phase.

[0043] As shown in Figure 5(a), the signal processing device 16 pre-sets the position where the displacement spot 21C appears as an analysis area K in the lock-in image G3 generated based on the X-ray image G0. The analysis area K may be a single area or multiple areas. The signal processing device 16 acquires coordinate information of the focal point P in the semiconductor device D from, for example, the focusing optical system 12 or the stage 14. As shown in Figure 5(b), the signal processing device 16 generates a mapping image G4 that associates the brightness values ​​of the analysis area K in each lock-in image G3 acquired while moving the focal point P with the coordinate information of the focal point P.

[0044] Computer 17 is a device that analyzes the cause of failure of semiconductor device D based on the output signal Sk output from signal processing device 16. Physically, computer 17 is composed of memory such as RAM and ROM, a processor (arithmetic circuit) such as a CPU, a communication interface, a storage unit such as a hard disk, and a display unit such as a display. Examples of computer 17 include personal computers, cloud servers, and smart devices (smartphones, tablet terminals, etc.). Computer 17 functions as an analysis unit that analyzes the cause of failure of semiconductor device D by executing a program stored in memory on the CPU of the computer system.

[0045] The computer 17 as an analysis unit has, for example, a threshold value for the amplitude of the detection signal Sd, and determines that there is a possibility that a location where the value of the amplitude indicated by the output signal Sk exceeds the threshold value is a factor of the failure cause of the semiconductor device D.

[0046] When the computer 17 as an analysis unit generates the lock-in image G3, it analyzes the failure cause and the like of the semiconductor device D based on the lock-in image G3. In this case, the computer 17 analyzes the failure cause and the like of the semiconductor device D to be analyzed, for example, by discriminating the light and shade of the contrast due to the periodic heat generation in the lock-in image G3.

[0047] When the computer 17 as an analysis unit generates the mapping image G4, it analyzes the failure cause and the like of the semiconductor device D based on the mapping image G4. In this case, the computer 17 has, for example, a threshold value for the luminance value, and when at least one luminance value of each coordinate included in the mapping image G4 exceeds the threshold value, for example, it determines that there is a possibility that the location corresponding to the coordinate is a factor of the failure cause of the semiconductor device D.

[0048] FIG. 6 is a flowchart showing an analysis method according to an embodiment of the present disclosure. The analysis method according to this embodiment is implemented using the above-described analysis device 1. As shown in FIG. 6, this analysis method includes an input step S01, an X-ray irradiation step S02, a detection step S03, a signal processing step S04, and an analysis step S05.

[0049] The input step S01 is a step of inputting a test signal St having a predetermined frequency F to the semiconductor device D. In this embodiment, in the input step S01, a test signal St having a predetermined frequency F is input from the tester 10 to the semiconductor device D. Also, a test signal St having a predetermined frequency F is input from the tester 10 to the signal processing device 16.

[0050] X-ray irradiation step S02 is a step in which X-rays R are irradiated onto the semiconductor device D. In X-ray irradiation step S02, the semiconductor device D is scanned by the stage 14 while the X-rays R output from the X-ray irradiation device 11 are focused by the focusing optical system 12. Input step S01 and X-ray irradiation step S02 may be started simultaneously.

[0051] In detection step S03, X-rays from the semiconductor device D due to irradiation with X-ray R are detected, and a detection signal Sd is output based on the detection result. In detection step S03, at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays from the semiconductor device D due to irradiation with X-ray R is detected. In this embodiment, transmitted X-rays Rt from the semiconductor device D are detected, and an X-ray image G0 based on the transmitted X-rays Rt is output as a detection signal.

[0052] The signal processing step S04 is a step in which a signal processing operation is performed on the detection signal Sd based on a predetermined frequency F. In the signal processing step S04, a component corresponding to the predetermined frequency F is extracted from the detection signal Sd, and an output signal Sk indicating the extracted component is output to the computer 17. In this embodiment, a time-series image G1 included in each frame of the X-ray image G0 is weighted based on the predetermined frequency F, and a lock-in image G3 is generated by integrating images G2 at the same timing in the time-series image G1 of each frame after weighting. In the signal processing step S04, a predetermined analysis area K may be set in the X-ray image G0, and a mapping image G4 may be generated that associates the brightness value of the X-ray image G0 in the analysis area K with the irradiation position of the X-ray R on the semiconductor device D.

[0053] Analysis step S05 is a step in which the cause of failure of semiconductor device D is analyzed based on the output signal Sk. In analysis step S05, for example, the amplitude of the detection signal Sd is compared with a threshold to analyze the cause of failure of semiconductor device D. If a lock-in image G3 is generated in signal processing step S04, analysis step S05 analyzes the cause of failure of semiconductor device D based on the lock-in image G3. If a mapping image G4 is generated in signal processing step S04, analysis step S05 analyzes the cause of failure of semiconductor device D based on the mapping image G4.

[0054] As explained above, the analysis device 1 can capture periodic structural changes within the semiconductor device D caused by heat generated by the input of the test signal St as changes in X-rays from the semiconductor device D. By using X-rays R, it is possible to observe the inside of the semiconductor device D in depth, even if the wiring layers of the semiconductor device D are multilayered. Furthermore, in the analysis device 1, the detection signal Sd is processed based on a predetermined frequency F used for the test signal St. This improves the signal-to-noise ratio of the output signal Sk used for analysis, even if the response of the semiconductor device D to X-rays R is weak.

[0055] In this embodiment, the signal processing device 16 extracts a component corresponding to a predetermined frequency F from the detected signal Sd. In this case, by extracting a component corresponding to the predetermined frequency F used in the test signal St from the detected signal Sd, the signal-to-noise ratio of the output signal Sk used for analysis can be improved more reliably.

[0056] In this embodiment, the detector 15 detects at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays from the semiconductor device D due to irradiation with X-rays R. In this case, periodic structural changes within the semiconductor device D due to heat generated by the input of the test signal St can be captured as changes in at least one of the transmitted X-rays, fluorescent X-rays, and scattered X-rays. By detecting at least one of the transmitted X-rays, fluorescent X-rays, and scattered X-rays, failure analysis of the semiconductor device D can be performed with high accuracy.

[0057] In this embodiment, the detector 15 is a two-dimensional X-ray detector such as a flat-panel X-ray detector, and outputs an X-ray image G0 based on X-rays from the semiconductor device D as a detection signal Sd. In this case, failure analysis of the semiconductor device D can be performed with high accuracy by analyzing the X-ray image G0.

[0058] In this embodiment, the signal processing device 16 weights the time-series images G1 contained in each frame of the X-ray image G0 based on a predetermined frequency F, and generates a lock-in image G3 by integrating the images G2 at the same timing in the time-series images G1 of each weighted frame. In this case, the periodic structural changes within the semiconductor device D can be emphasized in the generated lock-in image G3. Therefore, failure analysis of the semiconductor device D can be performed with high accuracy.

[0059] In this embodiment, the signal processing device 16 sets a predetermined analysis area K in the X-ray image G0 and generates a mapping image G4 that associates the brightness values ​​of the X-ray image G0 in the analysis area K with the irradiation position of the X-ray R on the semiconductor device D. In this case, for example, brightness information of interference spots 21A and 21B associated with changes in the crystal lattice spacing of Si used in the substrate of the semiconductor device D can be imaged and captured. Therefore, minute structural changes in the Si crystal lattice can be observed with high accuracy.

[0060] 1...Analysis device, 10...Tester, 11...X-ray irradiation device, 15...Detector, 16...Signal processing device, D...Semiconductor device, F...Determined frequency, Sd...Detection signal, St...Test signal, R...X-ray, Rt...Transmission X-ray, G0...X-ray image, G1...Time-series image, G3...Lock-in image, K...Analysis area, G4...Mapping image.

Claims

1. An analysis apparatus comprising: a tester that inputs a test signal having a predetermined frequency to a semiconductor device; an X-ray irradiation device that irradiates the semiconductor device with X-rays; a detector that detects the X-rays from the semiconductor device due to the X-ray irradiation and outputs a detection signal based on the detection result; and a signal processing device that performs signal processing on the detection signal based on the predetermined frequency.

2. The analysis apparatus according to claim 1, wherein the signal processing device extracts a component corresponding to the predetermined frequency from the detection signal.

3. The analytical apparatus according to claim 1 or 2, wherein the detector detects at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays from the semiconductor device due to X-ray irradiation.

4. The analysis apparatus according to any one of claims 1 to 3, wherein the detector is a two-dimensional X-ray detector and outputs an X-ray image based on X-rays from the semiconductor device as the detection signal.

5. The analysis apparatus according to claim 4, wherein the signal processing device weights the time-series images included in each frame of the X-ray image based on the predetermined frequency, and generates a lock-in image by integrating the images at the same timing in the time-series images of each frame after weighting.

6. The analysis apparatus according to claim 4 or 5, wherein the signal processing device sets a predetermined analysis area in the X-ray image and generates a mapping image relating the brightness values ​​of the X-ray image in the analysis area to the irradiation position of the X-rays on the semiconductor device.

7. An analysis method comprising: an input step of inputting a test signal having a predetermined frequency to a semiconductor device; an X-ray irradiation step of irradiating the semiconductor device with X-rays; a detection step of detecting X-rays from the semiconductor device due to the X-ray irradiation and outputting a detection signal based on the detection result; and a signal processing step of performing signal processing on the detection signal based on the predetermined frequency.

8. The analysis method according to claim 7, wherein the signal processing step involves extracting a component corresponding to the predetermined frequency from the detection signal.

9. The analysis method according to claim 7 or 8, wherein the detection step detects at least one of transmitted X-rays, fluorescent X-rays, and scattered X-rays from the semiconductor device due to the irradiation of the X-rays.

10. The analysis method according to any one of claims 7 to 9, wherein the detection step outputs an X-ray image based on X-rays from the semiconductor device as the detection signal.

11. The analysis method according to claim 10, wherein the signal processing step involves weighting the time-series images included in each frame of the X-ray image based on the predetermined frequency, and generating a lock-in image by integrating the images at the same timing in the time-series images of each frame after weighting.

12. The analysis method according to claim 10 or 11, wherein the signal processing step involves setting a predetermined analysis area in the X-ray image and generating a mapping image that associates the brightness values ​​of the X-ray image in the analysis area with the irradiation position of the X-rays on the semiconductor device.

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