Semiconductor failure analysis device and semiconductor failure analysis method

Abstract

To improve the resolution of semiconductor failure analyzation equipment.SOLUTION: Semiconductor failure analyzation equipment comprises: a tester 2 which applies a stimulus signal to a semiconductor device 100; a light source 3 that generates illumination light L1 with which the semiconductor device 100 is irradiated; a solid immersion lens 4 which is located on the optical path of the illumination light L1; a light detection portion 5 which receives reflected light L2 and outputs a detection signal corresponding to the reflected light 2; an optical system 6 which is located between the light source 3 and the solid immersion lens 4 and emits illumination light L1 to the semiconductor device 100 via the solid immersion lens 4, and which is located between the solid immersion lens 4 and the light detection portion 5 and emits reflected light L2 received via the solid immersion lens 4 to the light detection portion 5; and a computer 7 which obtains information pertaining to a failure point of the semiconductor device 100 by using the detection signal. The light source 3 emits illumination light L1 having center wavelength of 880 nm to 980 nm inclusive. The solid immersion lens 4 is formed from GaAs.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a semiconductor failure analysis apparatus and a semiconductor failure analysis method. [Background technology]

[0002] Semiconductor devices are becoming increasingly miniaturized. To achieve this, improvements in exposure and patterning technologies are required. Furthermore, it is important to determine whether semiconductor devices manufactured using these technologies function properly, and if they do not function properly, to identify the cause of the malfunction.

[0003] Patent Documents 1 and 2 disclose devices for inspecting semiconductor devices. These inspection devices irradiate light onto a semiconductor device to which an electrical signal has been applied. The light irradiated onto the semiconductor device becomes reflected light according to the state of the semiconductor device. These inspection devices then use the reflected light to obtain information about the operating state of the semiconductor device. The inspection device of Patent Document 1 obtains information about the parts of the semiconductor device that are operating at a specified frequency. The inspection device of Patent Document 2 obtains information about heat sources generated at fault locations in the semiconductor device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-92514 [Patent Document 2] International Publication No. 2016 / 056110 Summary of the Invention [Problem to be solved by the invention]

[0005] In the technical field of semiconductor failure analysis devices, there is also a demand for further improvement in resolution in order to analyze finer regions.

[0006] Therefore, the present invention provides a semiconductor failure analysis apparatus and a semiconductor failure analysis method that can improve resolution. [Means for solving the problem]

[0007] One aspect of the present invention is a semiconductor failure analysis apparatus that analyzes fault locations in a semiconductor device by utilizing a response to a stimulus signal, and includes: a signal generation unit that applies the stimulus signal to the semiconductor device; a light source that generates irradiation light to be irradiated onto the semiconductor device; a solid immersion lens that is arranged on the optical path of the irradiation light; a photodetection unit that receives reflected light generated when the irradiation light is reflected by the semiconductor device and outputs a detection signal corresponding to the reflected light; an optical system that is arranged between the light source and the solid immersion lens and emits the irradiation light to the semiconductor device via the solid immersion lens, and is arranged between the solid immersion lens and the photodetection unit and emits the reflected light received via the solid immersion lens to the photodetection unit; and an analysis unit that obtains information regarding the fault location of the semiconductor device from the detection signal; wherein the light source emits irradiation light having a center wavelength of 880 nm or more and 980 nm or less, and the solid immersion lens is formed of gallium arsenide (GaAs).

[0008] This semiconductor failure analysis device irradiates the semiconductor device with irradiation light having a central wavelength of 880 nm or more and 980 nm or less through a solid immersion lens formed from gallium arsenide when identifying the location of a failure in a semiconductor device to which a stimulus signal has been applied. Irradiation light having a central wavelength of 880 nm or more and 980 nm or less sufficiently penetrates the semiconductor device being analyzed, thereby obtaining reflected light with a light intensity sufficient to identify the location of the failure. Furthermore, the refractive index of the solid immersion lens formed from gallium arsenide is higher than that of air, allowing for an increased numerical aperture (NA). As a result, the spot diameter of the irradiation light can be reduced, thereby improving resolution.

[0009] In one embodiment, the light source may emit irradiation light having a center wavelength of 900 nm or more and 960 nm or less. This configuration can suitably improve the resolution.

[0010] In one embodiment, the analysis unit may include a heat source location identification unit that identifies a location of a heat source generated in the semiconductor device in response to the stimulus signal based on the detection signal and the stimulus signal. With this configuration, it is possible to identify the location of a heat source generated inside the semiconductor device.

[0011] In one embodiment, the analyzer may include an operating frequency determiner, and the operating frequency determiner may determine, based on the detection signal and the stimulus signal, a position at which the semiconductor device operates at a predetermined frequency that occurs in the semiconductor device in response to the stimulus signal. With this configuration, it is possible to determine the position at which the semiconductor device operates at the predetermined frequency that occurs in the semiconductor device. [Effects of the Invention]

[0012] According to the present invention, a semiconductor failure analysis apparatus and a semiconductor failure analysis method capable of improving resolution are provided. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a block diagram showing components of a semiconductor failure analysis device. [Figure 2] FIG. 2 is a diagram for explaining an example of a means for identifying a fault location in a semiconductor device. [Figure 3] FIG. 3 is a graph showing the relationship between the wavelength of light and the light transmittance for each material constituting the solid immersion lens. [Figure 4] FIG. 4 is a graph showing the relationship between the wavelength of light and the refractive index for each material that constitutes the solid immersion lens. [Figure 5] FIG. 5 is a graph showing the relationship between the wavelength of light and the light transmittance of a solid immersion lens formed from gallium arsenide. [Figure 6] FIG. 6 is a graph showing the optical transparency of silicon. DETAILED DESCRIPTION OF THE INVENTION

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicated explanations will be omitted.

[0015] 1, the semiconductor failure analysis apparatus identifies a failure location in an object under test such as a semiconductor device 100. In the following description, the semiconductor failure analysis apparatus will be simply referred to as analysis apparatus 1.

[0016] Examples of the semiconductor device 100 include integrated circuits having a PN junction such as a transistor (e.g., small-scale integrated circuits (SSI: Small Scale Integration), medium-scale integrated circuits (MSI: Medium Scale Integration), large-scale integrated circuits (LSI: Large Scale Integration), very large-scale integrated circuits (VLSI: Very Large Scale Integration), ultra-large-scale integrated circuits (ULSI: Ultra Large Scale Integration), and giga-scale integrated circuits (GSI: Giga Scale Integration)), power devices such as high-current / high-voltage MOS transistors and bipolar transistors, and memory storage devices.

[0017] The object to be inspected is not limited to the diced semiconductor device 100. The object to be inspected may be a semiconductor wafer on which a plurality of semiconductor devices 100 are formed.

[0018] FIG. 2 is a diagram conceptually illustrating a method for identifying a fault location. The semiconductor device 100 shown in FIG. 2 is arranged in the analysis apparatus 1, with the surface receiving the irradiated light L1 facing upward. The semiconductor device 100 has a layered structure including, for example, a protective layer 101, a wiring layer 102, a process layer 103, an insulating layer 104, and a substrate 105. The wiring layer 102 includes a wiring pattern made of a metal such as gold or aluminum. The process layer 103 includes multiple electrical functional units such as MOS transistors 103a. The substrate 105 is formed of silicon and has a thickness of 50 nm to 200 nm, for example, 80 nm. When light is irradiated onto the semiconductor device 100, the light is transmitted through some layers and reflected from other layers. For example, when light is irradiated from the substrate 105 side, the light may be transmitted through the substrate 105 and the insulating layer 104 and reflected from the process layer 103.

[0019] The intensity of the reflected light is generally smaller than the intensity of the irradiated light L1. That is, the intensity of the reflected light is attenuated by factors that the light encounters while passing through the substrate 105 and the insulating layer 104. For example, the intensity is affected by the optical transparency of the material constituting the substrate 105. The intensity of light may also be affected by the refractive index of the material constituting the optical path. Furthermore, the intensity of light may also be affected by the electric field formed in the layers constituting the optical path. Therefore, the ratio of the intensity of the reflected light to the intensity of the incident light is defined as the apparent reflectance. Because changes in reflectance reflect the influence of changes in the refractive index and the electric field, obtaining the reflectance distribution can reveal the internal state of the semiconductor device 100. For example, when a high-resistance portion 102a occurs in the wiring layer 102 and Joule heat is generated in that portion, a portion 105a occurs in the insulating layer 104 and the substrate 105, where the temperature rises due to Joule heat, causing a change in the refractive index. This change in refractive index manifests itself as a change in reflectance. In other words, knowing the reflectance distribution makes it possible to identify the location of abnormal heat generation (i.e., the location of the fault).

[0020] 1 , the analysis apparatus 1 includes a tester 2 (signal generating unit), a light source 3, a solid immersion lens 4, a light detecting unit 5, an optical system 6, and a computer 7. The analysis apparatus 1 may also include other additional components. For example, the analysis apparatus 1 may include a stage that moves the semiconductor device 100 relative to the optical system 6.

[0021] The tester 2 outputs a stimulus signal. The tester 2 is connected to the semiconductor device 100 and applies the stimulus signal to the semiconductor device 100. The tester 2 generates the stimulus signal based on a control signal input from the computer 7. The tester 2 starts and stops outputting the stimulus signal based on the control signal. The characteristics of the stimulus signal may be determined depending on the mode of analysis. Alternatively, a power supply, a pulse generator, or the like may be used as the tester 2.

[0022] For example, one type of analysis involves identifying the location of a heat source. In this case, the tester 2 applies a relatively low-frequency modulation current as a stimulus signal. For example, if the semiconductor device 100 contains a short circuit, the modulation current causes the short circuit to generate heat. As a result, a heat source is generated in the semiconductor device 100. The temperature of the heat source, which generates heat due to the modulation current, changes periodically depending on the frequency of the modulation current. The temperature change affects the refractive index of the material surrounding the heat source and through which the irradiated and reflected light passes. This change in refractive index causes a change in the intensity of the reflected light, resulting in a change in reflectivity, which is the ratio of the intensity of the reflected light to the intensity of the irradiated light. By using the change in reflectivity caused by the temperature change of the heat source as a response to the stimulus signal, the short circuit, which is an example of a fault location in the semiconductor device 100, can be identified.

[0023] For example, another type of analysis involves identifying the location of a circuit operating at a target frequency. Known examples of such analysis techniques include optical probing techniques known as EOP (Electro-Optical Probing) and EOFM (Electro-Optical Frequency Mapping). In optical probing, a light source irradiates an integrated circuit, and an optical sensor detects the light reflected by the integrated circuit to obtain a detection signal. A target frequency is then selected from the obtained detection signal, and its amplitude energy is displayed over time or as a two-dimensional map. In other words, optical probing techniques analyze the semiconductor device 100 for failures based on the intensity modulation of light from the semiconductor device 100 while it is operating. To achieve this, the tester 2 applies an electrical signal having a predetermined modulation frequency to the semiconductor device 100. In this case, the modulation frequency is often higher than the frequency of the stimulus signal used in the analysis to identify the heat source location. For example, the tester 2 applies a drive current having a frequency equivalent to the drive signal of the semiconductor device 100 as the stimulus signal.

[0024] As described above, there are several types of analysis modes. However, the differences are in the mode of the stimulus signal applied to the semiconductor device 100 and the processing of the detection signal obtained in response to the stimulus signal. In other words, even if the mode of analysis differs, there is generally no difference in the configuration of the analysis device 1.

[0025] The light source 3 generates the irradiating light L1. The central wavelength of the irradiating light L1 may be 880 nm or more and 980 nm or less. The irradiating light L1 may have a bandwidth of about 20 nm for such a central wavelength. Furthermore, the central wavelength of the irradiating light L1 may be 900 nm or more and 960 nm or less. The irradiating light L1 may have a bandwidth of about 20 nm for such a central wavelength.

[0026] The light source 3 may be configured as appropriate to emit irradiation light L1 having the above-described wavelength characteristics. For example, the light source 3 may be configured with an SLD (Super Luminescent Diode), an LED (Light Emitting Diode), or an incoherent light source that combines a lamp light source with an optical filter such as a bandpass filter. The light source 3 may also be a laser light source such as an LD (Laser Diode). The irradiation light L1 may be CW light or pulsed light.

[0027] The illumination light L1 output from the light source 3 is first incident on the optical system 6. The optical system 6 guides the illumination light L1 to the solid immersion lens 4. For example, the optical system 6 includes a polarizing beam splitter 61 and an objective lens 62. In addition to these, the optical system 6 may appropriately employ other optical components for the illumination light L1. For example, the optical system 6 may include an optical scanner for changing the irradiation position of the illumination light L1 on the semiconductor device 100. The optical scanner is, for example, a galvanometer mirror scanner, a polygon mirror scanner, or a MEMS mirror scanner, and guides the illumination light L1 to a desired position on the semiconductor device 100. The illumination light L1 output from the optical system 6 is irradiated onto the semiconductor device 100 via the solid immersion lens 4. More specifically, the illumination light L1 is irradiated onto a measurement point set on the semiconductor device 100.

[0028] The solid immersion lens 4 has a hemispherical or hyperhemispherical shape and is arranged so as to be in close optical contact with the semiconductor device 100. The solid immersion lens 4 irradiates the illumination light L1 while concentrating it onto the position to be analyzed on the semiconductor device 100. Therefore, the solid immersion lens 4 is made of a material that is transparent to the illumination light L1 that is irradiated onto the semiconductor device 100 and the reflected light L2 that is emitted from the semiconductor device 100.

[0029] As such a material, the solid immersion lens 4 employs gallium arsenide (GaAs). Hereinafter, optical transmittance as an optical characteristic of GaAs will be explained. FIG. 3 shows the optical transmittance of GaAs. In addition, FIG. 3 also shows the optical transmittance of gallium phosphide (GaP) and silicon (Si) as comparative examples. The horizontal axis represents the wavelength of light, and the vertical axis represents the optical transmittance. Graphs G3a to G3e show the optical transmittance of GaAs. Graph G3f shows the optical transmittance of GaP. Graph G3g shows the optical transmittance of Si.

[0030] Graphs G3a to G3e show that GaAs transmits light with wavelengths longer than 850 nm. More specifically, GaAs has a band where the optical transmittance changes rapidly relative to the wavelength of light. The wavelengths within this band are also referred to simply as the cutoff wavelength. The cutoff wavelength of GaAs is, for example, in the range of 880 nm to 980 nm. As the wavelength of light shifts from short wavelengths to long wavelengths, the optical transmittance increases rapidly from 0% to over 80%. Furthermore, the relationship between the optical transmittance and the wavelength of light also changes depending on the temperature of GaAs. Graphs G3a to G3e show the optical transmittance at temperatures of 0°C (Graph G3a), 50°C (Graph G3b), 100°C (Graph G3c), 150°C (Graph G3d), and 200°C (Graph G3e), respectively. In other words, as the temperature of GaAs increases, the cutoff wavelength where the optical transmittance changes rapidly shifts toward longer wavelengths.

[0031] For example, GaP is sometimes used as the material for solid immersion lenses. Referring to graph G3f, it can be seen that GaP transmits light with wavelengths longer than 500 nm. For example, the cutoff wavelength of GaP is generally within the range of 500 nm to 600 nm. In other words, the cutoff wavelength of GaP is shorter than the cutoff wavelength of GaAs. In other words, the cutoff wavelength of GaAs is longer than the cutoff wavelength of GaP.

[0032] Furthermore, for example, Si may also be used as the material for the solid immersion lens. Referring to graph G3g, it can be seen that Si transmits light with wavelengths longer than 1000 nm. For example, the cutoff wavelength of Si with a thickness that can be effectively used as a solid immersion lens is generally within the range of 1000 nm to 1200 nm. In other words, the cutoff wavelength of a Si solid immersion lens is longer than that of GaAs. In other words, the cutoff wavelength of GaAs is shorter than that of Si.

[0033] Next, we will explain the refractive index, which is another optical property of GaAs. Figure 4 shows the relationship between the refractive index and wavelength of GaAs, GaP, and Si. Graph G4a shows the refractive index of GaAs. Graph G4b shows the refractive index of GaP. Graph G4c shows the refractive index of Si. For example, according to graph G4a, the refractive index of GaAs is approximately 3.40 or more and 4.40 or less. For example, when the wavelength of incident light is 1064 nm, the refractive index of GaAs is 3.47. Also, when the wavelength of incident light is 940 nm, the refractive index of GaAs is 3.57.

[0034] The refractive index of GaAs is higher than that of GaP, for example, as shown in graph G4b. More specifically, the refractive index of GaAs is higher than that of GaP throughout the entire range from 500 nm to 1500 nm shown on the horizontal axis of FIG. 4. For example, when the wavelength of incident light is 780 nm, the refractive index of GaP is 3.21. Also, when the wavelength of incident light is 670 nm, the refractive index of GaP is 3.27. Therefore, GaAs is more advantageous than GaP in improving resolution due to its higher refractive index.

[0035] Referring again to Figure 1, light reflected at the measurement point in response to illumination light L1 (reflected light L2) passes through solid immersion lens 4 and objective lens 62 and enters polarizing beam splitter 61. At this time, by placing a short-pass filter in the optical path of reflected light L2, it is possible to block infrared light generated by semiconductor device 100. Furthermore, the light input to polarizing beam splitter 61 has its polarization direction tilted by passing through a λ / 4 plate twice, and therefore polarizing beam splitter 61 transmits the reflected light. Reflected light L2 emitted from polarizing beam splitter 61 is input to photodetector 5.

[0036] As described above, the optical system of this embodiment uses a confocal optical system and is configured to detect reflected light L2 from a limited focal range. As an element constituting the confocal optical system, a pinhole may be used, or an optical fiber may be used in which the refractive index difference between the core and cladding is utilized.

[0037] The photodetector 5 detects the light intensity of the reflected light L2 reflected by the semiconductor device 100 in response to the irradiated light L1. The photodetector 5 also converts the detected reflected light L2 into an analog detection signal and outputs it. The photodetector 5 is an avalanche photodiode (APD), a photodiode (PD), a photomultiplier tube (PMT), a silicon photomultiplier (SiPM), or the like.

[0038] The computer 7 includes a data analysis unit 71 that identifies a fault location in the semiconductor device 100 and a control unit 72 that controls the operation of various elements constituting the analysis apparatus 1. The computer 7 physically includes memory such as RAM and ROM, a processor (arithmetic circuit) such as a CPU, a communication interface, and a storage unit such as a hard disk. Examples of such computers 7 include personal computers, cloud servers, and smart devices (smartphones, tablet terminals, etc.). The computer 7 functions by executing a program stored in the memory on the CPU of the computer system. Furthermore, the data analysis unit 71 may include a processing unit according to the type of analysis. For example, the data analysis unit 71 includes a heat source location identification unit 71a and / or an operating frequency identification unit 71b. The heat source location identification unit 71a performs processing to identify the location of a heat source. The operating frequency identification unit 71b performs processing to identify the location of a semiconductor device operating at a predetermined frequency in response to the stimulus signal, based on the detection signal and the stimulus signal.

[0039] The control unit 72 also includes, for example, a light control unit 72a and a tester control unit 72b. The light control unit 72a outputs control signals to the light source 3 and the optical system 6. Examples of such control signals include a signal that drives an optical scanner to scan the irradiated light L1. The tester control unit 72b also outputs control signals for controlling stimulus signals that are output from the tester 2 to the semiconductor device 100.

[0040] <Action and effect> When identifying a fault location in a semiconductor device 100 to which a stimulus signal has been applied, this analysis device 1 irradiates the semiconductor device 100 with illumination light L1 having a central wavelength of 880 nm or more and 980 nm or less via a solid immersion lens 4 formed from GaAs. The illumination light L1 having a central wavelength of 880 nm or more and 980 nm or less is sufficiently transmitted through the semiconductor device 100, which is the object of analysis and is formed from silicon. As a result, reflected light L2 having an optical intensity sufficient to identify the fault location can be obtained. Furthermore, since the refractive index of the solid immersion lens 4 formed from GaAs is higher than the refractive index of air and GaP, the numerical aperture (NA) can be increased. As a result, it is possible to reduce the spot diameter of the illumination light L1, thereby improving the resolution.

[0041] When a stimulus signal is applied to the semiconductor device 100, heat is generated in the pattern wiring and electrical functional parts regardless of the form of the stimulus signal. The degree of heat generation tends to increase at the fault location. In an analysis that utilizes such heat generation, the combination of irradiating light L1 with a central wavelength of 880 nm or more and 980 nm or less and a solid immersion lens 4 formed from GaAs is particularly advantageous.

[0042] Like FIG. 3, FIG. 5 shows the relationship between the wavelength and the optical transmittance of GaAs. FIG. 5 shows an enlarged view of the range from 890 nm to 960 nm. Graphs G5a to G5f show the optical transmittance when the temperature of GaAs is 60°C (graph G5a), 70°C (graph G5b), 80°C (graph G5c), 90°C (graph G5d), 100°C (graph G5e), and 110°C (graph G5f), respectively. For example, assume that the wavelength of the irradiated light L1 is 920 nm and the temperature of the solid immersion lens 4 changes between 60°C and 110°C. In this case, the optical transmittance of the solid immersion lens 4 changes in the range from 5% to 70%. In other words, the optical transmittance of the solid immersion lens 4 changes significantly depending on the temperature of the solid immersion lens 4.

[0043] The irradiated light L1 and reflected light L2 pass not only through the substrate 105 of the semiconductor device 100, etc., but also through the solid immersion lens 4. As they pass through this solid immersion lens 4, the irradiated light L1 and reflected light L2 are affected by changes in light transmittance due to temperature changes in the solid immersion lens 4. That is, the irradiated light L1 and reflected light L2 are affected by changes in light transmittance of the solid immersion lens 4, in addition to the influence of the refractive index of the semiconductor device 100, whose temperature has changed due to heat emitted from the heat source. As a result, the light intensity of the reflected light L2 changes significantly due to heat generation, and the change in reflectance also becomes significant. As a result, even slight differences in temperature at each measurement position appear as large changes in reflectance, making it possible to improve temperature resolution.

[0044] In short, the central wavelength of the irradiation light L1 is included in the band of the cutoff frequency of GaAs, and therefore the temperature resolution is improved. In other words, the central frequency of the irradiation light L1 may be set to a value that results in a large change in light transmittance in a temperature range that includes normal temperatures and abnormal temperatures. For example, if a normal temperature is 60°C and a temperature of 100°C or higher is judged to be abnormal, the central wavelength may be set to 920 nm. This is because, with such a setting, a phenomenon occurs in which the reflectance drops significantly when a heat source that heats the solid immersion lens 4 to 100°C or higher is present.

[0045] Furthermore, by combining irradiated light L1 having a central wavelength of 880 nm or more and 980 nm or less with a solid immersion lens 4 formed from GaAs, it is possible to obtain reflected light L2 having a light intensity sufficient for analysis. For example, as shown in FIG. 2, irradiated light L1 and reflected light L2 are attenuated according to the light transmittance of silicon when passing through substrate 105. Graph G6 in FIG. 6 shows the relationship between the thickness of substrate 105 formed from silicon and light transmittance. Graph G6 also shows the light transmittance when the wavelength of light is 940 nm. The horizontal axis represents the thickness of substrate 105. The vertical axis represents light transmittance. As shown in FIG. 6, as the thickness of substrate 105 increases, the light transmittance decreases.

[0046] For example, when the thickness of the substrate 105 of the semiconductor device 100 is 80 μm, which is a commonly used thickness, the light transmittance is approximately 23%. Furthermore, when the thickness of the substrate 105 of the semiconductor device 100 is 40 μm, the light transmittance is approximately 48%. These light transmittances enable the generation of reflected light L2 with sufficient light intensity for various analyses. In other words, there is no need to thin the substrate 105 by polishing or other processes in order to obtain reflected light L2 with sufficient light intensity. As a result, when performing failure analysis of the semiconductor device 100, additional work such as polishing the substrate 105 is not required, thereby simplifying the failure analysis. Furthermore, thinning the substrate 105 makes handling of the semiconductor wafer difficult. However, according to this embodiment, even a semiconductor device 100 with a commonly used substrate thickness can be analyzed without polishing the substrate 105, thereby making the semiconductor wafer easier to handle.

[0047] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

[0048] For example, in the above embodiment, the arrangement of the optical system 6 and solid immersion lens 4 relative to the semiconductor device 100 is exemplified as a configuration in which irradiated light L1 is provided to the substrate 105 side of the semiconductor device 100, and reflected light L2 output from the substrate 105 side is detected. For example, irradiated light L1 may be provided to the semiconductor device from above (the protective layer 101 side in FIG. 2). In this case, the solid immersion lens 4 is installed on the protective layer 101 of the semiconductor device 100. Alternatively, the semiconductor device 100 may be configured to be irradiated with inspection light from either the above or below, and to detect electromagnetic waves from the other side. In this case, the solid immersion lenses 4 are installed on both the above and below sides of the semiconductor device. [Explanation of symbols]

[0049] 1...analysis device (semiconductor failure analysis device), 2...tester (signal generation unit), 3...light source, 4...solid immersion lens, 5...light detection unit, 6...optical system, 7...computer (analysis unit), 61...polarizing beam splitter, 62...objective lens, 71...data analysis unit, 71a...heat source position identification unit, 71b...operating frequency identification unit, 72...control unit, 72a...light control unit, 72b...tester control unit, 100...semiconductor device, L1...irradiated light, L2...reflected light.

Claims

1. A semiconductor failure analysis apparatus that analyzes a failure location contained in a semiconductor device using a response to a stimulus signal, a signal generating unit that applies a stimulus signal to the semiconductor device; a light source that generates illumination light, which is CW light, that is irradiated onto the semiconductor device; a solid immersion lens disposed on the optical path of the irradiation light; a light detection unit that receives reflected light generated when the irradiated light is reflected by the semiconductor device, and outputs a detection signal corresponding to the reflected light that has been affected by a response of the semiconductor device to the stimulus signal; an optical system that is disposed between the light source and the solid immersion lens, and emits the irradiation light to the semiconductor device via the solid immersion lens, and that is disposed between the solid immersion lens and the light detection unit, and emits the reflected light received via the solid immersion lens to the light detection unit; an analysis unit that obtains information about a fault location in the semiconductor device from the detection signal, the light source emits the irradiation light having a center wavelength of 880 nm or more and 980 nm or less, The semiconductor failure analysis device, wherein the solid immersion lens is formed of gallium arsenide (GaAs), the light transmittance of which changes depending on the temperature.

2. 2. The semiconductor failure analysis device according to claim 1, wherein the irradiated light has a center wavelength of 900 nm or more and 960 nm or less.

3. 3. The semiconductor failure analysis device according to claim 1, wherein the irradiated light has a bandwidth of 20 nm with respect to a center wavelength.

4. the analysis unit has a heat source position identification unit, 4. The semiconductor failure analysis apparatus according to claim 1, wherein the heat source position identifying unit identifies a position of a heat source generated in the semiconductor device in response to the stimulus signal based on the detection signal and the stimulus signal.

5. the analysis unit has an operating frequency identification unit, the operating frequency identifying unit identifies a position where the semiconductor device operates at a predetermined frequency generated in response to the stimulus signal, based on the detection signal and the stimulus signal.

4. The semiconductor failure analysis device according to claim 1.

6. A semiconductor failure analysis method for analyzing a failure location in a semiconductor device using a response to a stimulus signal, comprising: a signal applying step of applying a stimulus signal to the semiconductor device; a light irradiation step of irradiating the semiconductor device with irradiation light that is CW light and has a central wavelength of 880 nm or more and 980 nm or less; a light detection step of receiving reflected light generated when the irradiated light is reflected by the semiconductor device, and outputting a detection signal corresponding to the reflected light affected by a response of the semiconductor device to the stimulus signal; an analysis step of obtaining information about a fault location in the semiconductor device from the detection signal, In the light irradiation step, the irradiation light is emitted to the semiconductor device through a solid immersion lens arranged on an optical path of the irradiation light; In the light detection step, the reflected light is detected via the solid immersion lens; The semiconductor failure analysis method, wherein the solid immersion lens is formed of gallium arsenide (GaAs), the light transmittance of which changes depending on the temperature.

7. 7. The semiconductor failure analysis method according to claim 6, wherein the irradiated light has a center wavelength of 900 nm or more and 960 nm or less.

8. 8. The semiconductor failure analysis method according to claim 6, wherein the irradiated light has a bandwidth of 20 nm with respect to a center wavelength.

9. 9. The semiconductor failure analysis method according to claim 6, wherein the semiconductor device has a substrate having a thickness of 50 nm or more and 200 nm or less.

10. 10. The semiconductor failure analysis method according to claim 6, wherein the response of the semiconductor device to the stimulus signal is a change in the refractive index of the semiconductor device.

11. 11. The semiconductor failure analysis method according to claim 10, wherein the analyzing step identifies a position of a heat source occurring in the semiconductor device based on the detection signal and the stimulus signal.

12. 10. The semiconductor failure analysis method according to claim 6, wherein the response of the semiconductor device to the stimulus signal is an operation of a predetermined frequency occurring in the semiconductor device.

13. the analyzing step identifies a position where the semiconductor device operates at a predetermined frequency based on the detection signal and the stimulus signal. The semiconductor failure analysis method according to claim 12.

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