Short-wave infrared light emission and fluorescence confocal microscopic system for integrated circuit detection

Abstract

The invention relates to a microscope system, in particular to a confocal microscope system of a short-wave infrared band. The system comprises a bright / dark field microscopy subsystem, a photon emission microscopy subsystem, a short wave infrared laser scanning confocal microscopy subsystem, a fluorescence confocal microscopy subsystem and a control module. According to the system provided by the invention, the short-wave infrared fluorescence lifetime curve can be obtained through the electro-luminescence emission and / or photoluminescence emission of the semiconductor device in the integrated circuit, so that the defect type of the semiconductor can be judged. Besides, the system adopts a multi-subsystem optical path multiplexing structure in structural design, short-wave infrared fluorescence generated by exciting a defect or a failure point is collected while observation is facilitated, high integration level is achieved, and observation, positioning and failure analysis of the defect or the failure point can be achieved only by using a single system provided by the invention.

Description

Technical Field

[0001] The present invention relates to a microscope system, and particularly to a confocal microscope system in the short-wave infrared band. Background Art

[0002] During the production or use of integrated circuits, the defects or failure problems generated by chips and their mechanisms need to be detected more quickly, and the causes of failure need to be found out. Traditional detection methods judge the existence of faults by performing electrical measurements on semiconductor wafers or bare chips, and provide basic data for subsequent failure analysis. However, to trace the source of faults, traditional electrical tests alone are far from enough. It is necessary to accurately locate the defect position and reconstruct the failure scenario in order to deeply understand the failure mechanism. With the improvement of chip integration, the number of layers increases, the circuits become more refined, and the operating voltage continues to decrease, which poses extremely high requirements for the performance of electrical detection.

[0003] While the improvement of integration brings stronger chip performance, it also amplifies the failure risk. Once a fault occurs, its causes are often intricate and complex, and it is necessary to combine various refined detection methods and functional modules such as mechanical testing, electron beam testing (EBT), and X-ray imaging for location analysis. This leads to the complication of the operation process. When switching instruments, it is necessary to frequently move specific faulty samples, increasing the risk of sample contamination and damage.

[0004] Current chip failure detection technologies include destructive methods that require sample cutting, ranging from ordinary optical microscopes to transmission electron microscopes (TEM) and scanning electron microscopes (SEM). Although these methods can effectively deal with various defects, due to the fact that different defects and failure problems may occur after a chip is damaged, the irreversibility of sample cutting makes it difficult to restore the failure mode, and there are challenges in determining the true cause of failure. Therefore, a non-destructive and high-precision detection means is needed.

[0005] For integrated circuit manufacturers or research institutions, considering economic benefits or production costs, samples with defects or failure problems are very precious. They often hope to locate and discover problems through non-destructive means and the least detection cost, make a more comprehensive location, analysis and judgment of the defects, classify and summarize the mechanisms of their occurrence, and feedback them to the corresponding design, production or use stages to avoid the same situation. However, using a general optical microscope system can only analyze based on morphology and cannot truly achieve the functional detection of integrated circuit devices. Therefore, achieving non-destructive detection has become a major problem faced by the failure location analysis system. Summary of the Invention

[0006] The present invention innovatively proposes a highly integrated microscopic system that can provide feedback on the type of defects by collecting the short-wave infrared fluorescence lifetime through the self-light emission and photoluminescence of semiconductors. Utilizing the light-transmitting characteristics of silicon in the short-wave infrared band and the principle of stimulated emission, and through highly sensitive weak-light detection means, the weak short-wave infrared light signals emitted by the fault point under electrical excitation and optical excitation are detected to accurately locate the failed device.

[0007] The technical solution provided by the present invention is: a short-wave infrared light emission and fluorescence confocal microscopic system for integrated circuit detection, including a bright / dark field microscopic subsystem, a photon emission microscopic subsystem, a short-wave infrared laser scanning confocal microscopic subsystem, a fluorescence confocal microscopic subsystem, and a control module; the bright / dark field microscopic subsystem observes the sample through vertical illumination by a bright field light source or diffuse reflection by a dark field light source; the photon emission microscopic subsystem tests the integrated circuit to be measured by driving; after the short-wave infrared laser scanning confocal microscopic subsystem focuses the short-wave infrared laser on the sample, the reflected light is captured by a deeply cooled InGaAs imager after passing through a beam splitter and a focusing lens; the laser emitted by the fluorescence confocal subsystem passes through a dichroic mirror and enters a short-wave infrared microscopic objective lens, converges to the surface of the sample, and realizes the detection of the short-wave infrared fluorescence lifetime; the control module is used to control the data acquisition and working modes of each subsystem, and process the acquired data to realize the determination of sample defects or failures.

[0008] Preferably, the bright / dark field microscopic subsystem includes a bright field light source, a dark field light source, a lens with a focal length of 200 mm and a lens with a focal length of 75 mm, a beam splitter, and an objective lens; the bright field light source vertically irradiates the test sample after passing through the lens with a focal length of 75 mm and the beam splitter; the dark field light source is arranged diagonally above the sample stage.

[0009] Preferably, the short-wave infrared laser scanning confocal microscopic subsystem includes a 1310 nm laser, a lens with a focal length of 250 mm and a lens with a focal length of 25.4 mm, a beam splitter, a fast steering mirror, a scanning lens, a tube lens, and a deeply cooled InGaAs imager; the telecentric system composed of the scanning lens and the tube lens ensures that the objective aperture is always fully illuminated when the fast steering mirror moves.

[0010] Preferably, the fluorescence confocal subsystem includes a 660 nm laser, a lens with a focal length of 200 mm and a lens with a focal length of 25.4 mm, a dichroic mirror, and a partial laser confocal optical path; the dichroic mirror is of the long-pass type and transmits wavelengths above 980 nm; the fluorescence excited after the laser focuses on the sample is transmitted through the optical path, and after passing through the dichroic mirror, the beam splitter, and the focusing lens with a focal length of 20.1 mm, the fluorescence lifetime is detected by a single-photon detector.

[0011] Preferably, the deep-cooled InGaAs imager includes a water-cooling module, a multi-stage thermoelectric cooler, and an InGaAs short-wave infrared imager; the cold end of the multi-stage thermoelectric cooler is connected to the water-cooling module, and the hot end is connected to the InGaAs short-wave infrared imager; the deep-cooled InGaAs imager obtains high-contrast tomographic images and three-dimensional structures of the failed device through the collaborative work of an emission microscope, a short-wave infrared laser, and a three-dimensional displacement stage.

[0012] Preferably, the system has four working modes: in the bright / dark field mode, only the wide-field light source is enabled for macroscopic detection of the sample to locate the region of interest or the failed part; in the emission microscope mode, the wide-field light source is turned off to capture the luminescence image of the failed device for precise positioning; in the laser confocal scanning mode, both the wide-field light source and the short-wave infrared laser are enabled. After determining the scanning range according to the size of the failed device, the wide-field light source is turned off, and two-dimensional high-contrast images and three-dimensional stereo images of the key devices of the sample are obtained by scanning with the displacement stage; in the fluorescence confocal mode, the red laser is retained, and time-correlated single-photon counting technology is used to collect fluorescence lifetime data.

[0013] Compared with the prior art, the system proposed by the present invention can obtain short-wave infrared fluorescence lifetime curves through the electroluminescence and / or photoluminescence of semiconductor devices in an integrated circuit, and thus can make a determination of the type of semiconductor defects. In addition, the system adopts a structure of optical path multiplexing of multiple subsystems in its structural design, which is convenient for observation while collecting short-wave infrared fluorescence generated by exciting defects or failure points, and has a high degree of integration. The observation, positioning, and failure analysis of defects or failure points can be realized only within the single system proposed by the present invention. Since the device sizes of silicon-based chip devices are generally tiny, the present invention selects a point scanning method to obtain more flexible control of the scanning size and direction. The present invention adopts a camera acquisition scheme, and all subsystems realizing the four modes adopt optical multiplexing design to form a coaxial system, which has good compactness. Description of the Drawings

[0014] Figure 1Schematic diagram of the hardware structure of the short-wave infrared light emission and fluorescence confocal microscopy system for integrated circuit detection in the embodiments of the present invention; in the figure, 101. 660nm laser; 102. 1310nm laser; 103. First lens; 104. Second lens; 105. Third lens; 106. Fourth lens; 107. Two-dimensional scanning galvanometer; 108. Scanning lens; 109. Sleeve lens; 110. Dichroic mirror; 111. First beam splitter; 112. Seventh lens; 113. Single photon detector; 114. Bright field light source; 115. Dark field light source; 116. Three-dimensional displacement platform; 117. Test sample; 118. Objective lens; 119. Piezoelectric ceramic sensor; 120. Second beam splitter; 121. Third beam splitter; 122. Fifth lens; 123. Sixth lens; 124. Deep-cooled InGaAs imager; Figure 2 Schematic diagram of the working principle and detection process of the short-wave infrared light emission and fluorescence confocal microscopy system for integrated circuit detection in the embodiments of the present invention. Detailed implementation manners

[0015] For ease of understanding of the present invention, the present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of the present invention more thorough and comprehensive.

[0016] The present invention proposes a highly integrated non-destructive testing system, which combines bright / dark field microscopy subsystem, light emission microscopy subsystem, laser scanning confocal microscopy subsystem and fluorescence confocal microscopy subsystem. Utilizing the transparent property of silicon in the short-wave infrared band and the principle of stimulated emission. The system mainly includes a wide-field illumination light source, a short-wave infrared laser with a wavelength of 1310 nm, a visible light laser with a wavelength of 660 nm, a deep-cooled single photon detector, a deep-cooled short-wave infrared imager, a three-dimensional displacement stage and optical lenses, and adopts an optical multiplexing structure to achieve the high integration of the system.

[0017] As Figure 1As shown in the figure, the bright / dark field microscopy subsystem includes a bright field module and a dark field module. The bright field module includes a bright field light source 114, a fifth lens 122 with a focal length of 200 mm, a sixth lens 123 with a focal length of 75 mm, a third beam splitter 121, an objective lens 118, a piezoelectric ceramic sensor 119, and a deep-cooled InGaAs imager 124. The test sample 117 is observed through vertical illumination by the bright field light source 114. The dark field module includes a dark field light source 115, the fifth lens 122, the third beam splitter 121, the objective lens 118, the piezoelectric ceramic sensor 119, and the deep-cooled InGaAs imager 124. The dark field light source 115 is arranged diagonally above the sample stage, and the sample is observed through diffuse reflection. The bright / dark field microscopy subsystem takes advantage of the good penetration of short-wave infrared light into silicon, combines the two illumination methods, and can perform non-contact non-destructive testing on unmetallized wafers or back-packaged chips according to requirements. The wide-field imaging of the macroscopic region by this subsystem also provides a working basis for subsequent precise defect localization.

[0018] The photoluminescence microscopy subsystem shows more unique advantages in the defect localization of integrated circuits. Especially in detecting tiny electrical performance anomalies and internal structure defects, it provides a more precise diagnostic tool. The core of the photoluminescence microscopy subsystem is the InGaAs short-wave infrared imager, which can not only conduct macroscopic observations on the failure area, but also monitor the weak light emission points in the field of view in real time to achieve precise localization of the failed device.

[0019] When observing integrated circuits or semiconductor devices in the bright / dark field microscopy subsystem, for integrated circuits with different manufacturing processes, corresponding objective lenses need to be selected for observation. As the magnification of the objective lens increases, its light passing aperture will decrease accordingly. At this time, it is necessary to correspondingly increase the gain and integration time of the imager to ensure the imaging quality. This also means that it is necessary to effectively suppress the influence of the thermal noise and readout noise of the imager on the imaging quality. In applications, due to the light intensity loss and the relatively low effective numerical aperture (NA) of the macro objective lens, there may be a certain difference between the relative signal intensity collected by each objective lens and the calculated value. The InGaAs detector has a good overlap in collecting short-wave infrared light signals and the spectra that can penetrate silicon devices, and can observe problems such as chemical impurities, physical defects, and recombination radiation. It is a better choice for the photoluminescence microscopy subsystem. The present invention has developed a deeply cooled InGaAs short-wave infrared imager with high detection efficiency for this system, which is used as the main detector of the short-wave infrared wide-field microscopy subsystem, the photoluminescence microscopy subsystem, and the laser confocal microscopy subsystem. The deeply cooled InGaAs short-wave infrared imager includes a water cooling module, a multi-stage thermoelectric cooler, and an InGaAs short-wave infrared imager; the cold end of the multi-stage thermoelectric cooler is connected to the water cooling module, and the hot end is connected to the InGaAs short-wave infrared imager. Through the cooperation of the water cooling module and the multi-stage thermoelectric cooler (TEC), cooling to -50 °C is achieved, effectively reducing the dark current and thermal noise, and reducing the generation of "hot" pixels and dead pixels. These methods significantly improve the overall imaging quality of the system and the signal-to-noise ratio of weak light detection.

[0020] The deeply cooled InGaAs short-wave infrared imager operates under a 5 V power supply, and the power consumption in the non-cooled state is only 2.5 W; the thermoelectric cooler (TEC) at the cooling end needs to be powered separately, and the power consumption is about 20 W. In addition, the operating frequency and integration time of the area array staring short-wave infrared imager can be flexibly adjusted: the operating frequency can be adjusted in the range of 100 kHz to 20 MHz, and the integration time can be adjusted between 100 ns and 100 s, and the maximum imaging frame rate can reach 244 fps. Select the 100× objective lens with the smallest light passing aperture, and under the non-cooled state and the condition of being cooled to -50 °C respectively, adjust to the same appropriate integration time (5 ms) to collect images of the same area of the wafer sample. The results show that due to the heat accumulation generated by its own operation, the actual operating temperature of the non-cooled imager is much higher than room temperature, so the collected images are significantly affected by thermal noise, seriously reducing the image quality. In contrast, after cooling to -50 °C, the thermal noise is effectively suppressed, significantly improving the imaging clarity and signal-to-noise ratio.

[0021] The photoluminescence microscopy subsystem and the bright / dark field microscopy subsystem use an optical path multiplexing structure. Through the photoluminescence characteristics of the device under bias conditions, combined with the bright / dark field microscopy images, efficient and rapid positioning of the failure points or defective devices in the integrated circuit is achieved.

[0022] The laser scanning confocal microscopy subsystem consists of a 1310 nm laser 102 with a power of 15 mW, a first lens 103 with a focal length of 250 mm, a second lens 104 with a focal length of 25.4 mm, a first beam splitter 111, a two-dimensional scanning galvanometer 107, a scanning lens 108, a sleeve lens 109, and a deep-cooled InGaAs short-wave infrared imager 124. The telecentric system formed by the scanning lens 108 and the sleeve lens 109 ensures that the objective aperture is always fully illuminated when the two-dimensional scanning galvanometer 107 moves. After the short-wave infrared laser is focused on the test sample 117, the reflected light is focused by the third beam splitter 121 and the fifth lens 122 and then captured by the deep-cooled InGaAs imager 124.

[0023] The fluorescence confocal subsystem includes a 660 nm laser 101 with a power of 120 mW, a third lens 105 with a focal length of 200 mm, a fourth lens 106 with a focal length of 25.4 mm, a dichroic mirror 110, and a partial laser confocal optical path (the first beam splitter) and a seventh lens 112. The dichroic mirror 110 is of the long-pass type and is designed to transmit wavelengths above 980 nm. The working process of this subsystem is as follows: The high-power 660 nm pulsed laser passes through the beam expander and collimator system and is collimated into a parallel beam. It passes through the spatial filter in the middle for filtering to obtain a Gaussian beam with a uniform spatial distribution, and then irradiates on the high-damage-threshold dichroic mirror. After transmission, it reaches the high-precision two-dimensional scanning galvanometer. The laser passes through the relay telecentric system composed of the scanning lens and the sleeve lens. The beam coming out of the telecentric system becomes a parallel beam again, passes through the beam splitter mirror and enters the short-wave infrared microscope objective, and converges to the surface of the test sample. The fluorescence excited after the laser focuses on the test sample is transmitted through the optical path, passes through the dichroic mirror 110, the first beam splitter 111, and the seventh lens 112 with a focal length of 20.1 mm, and then the fluorescence lifetime is detected by the single-photon detector (SPD) 113. The data of each subsystem are integrated and analyzed to finally achieve the rapid determination of this type of failure problem.

[0024] Another core of the fluorescence confocal subsystem is the single-photon detector 113. To improve the detection efficiency of the fluorescence excited by the test sample, the present invention adopts a low-noise short-wave infrared single-photon detector in the free-running mode based on a deep-cooled InGaAs negative-feedback avalanche diode (NFAD). It uses spatial optical coupling, and the photosensitive surface diameter is as high as 50 μm, which ensures the light collection efficiency and reduces the difficulty of optical path adjustment; the detection wavelength range is from 950 nm to 1650 nm, the peak detection efficiency can reach 25%, and the dark count rate is only about 3 kHz at a detection efficiency of 15%.

[0025] In an application, a chip may have different types of defects and failures for different reasons. For this, the system starts from integrated circuit detection, is based on the short-wave infrared band, and adopts an optical path multiplexing structure in the structural design, which not only meets the requirements of high integration of the system but also facilitates the collection of short-wave infrared fluorescence generated by excited defect or failure points. Finally, with the overall cooperation of the system, the failure mechanism can be judged more quickly by comparing the short-wave infrared fluorescence lifetime curves of defect or failure points.

[0026] Since the overall optical path of the system is coaxial and the short-wave infrared imager is the key imaging component, the 1310 nm laser can be turned on at this time. As an indication laser, the 660 nm laser is adjusted to the appropriate focal plane of the test sample at the imaging end to excite the integrated circuit unit to be measured. According to the reversibility of the optical path, the excited short-wave infrared fluorescence becomes parallel light after passing through the objective lens, converges after being reflected by the semi-transparent semi-reflective mirror, and then becomes parallel light again after passing through the sleeve lens and the scanning lens and irradiates the two-dimensional scanning galvanometer. The fluorescence passes through the dichroic mirror and the filter, and converges on the detection target surface through the aspherical lens. The time-correlated single photon counting technology is used by the single photon detector to measure information such as the short-wave infrared fluorescence lifetime generated by the failed device after laser excitation. By comparing the fluorescence lifetime curves of corresponding defects and combining effective information such as the characteristics, manufacturing process, and usage environment of the device under test, the defect type is analyzed. After the data of each subsystem are integrated and analyzed, the rapid determination of this type of failure problem is finally realized.

[0027] The system provided by the present invention can work in four modes: in the bright / dark field mode, only the wide-field light source is enabled for macroscopic detection of the chip to locate the region of interest or the failure part; in the emission microscope mode, the wide-field light source is turned off to capture the luminescence image of the failed device for precise positioning; in the laser scanning confocal scanning mode, both the wide-field light source and the short-wave infrared laser are enabled. After determining the scanning range according to the size of the failed device, the wide-field light source is turned off, and two-dimensional high-contrast images and three-dimensional stereoscopic images of the key devices of the chip are obtained by scanning with the displacement stage; in the fluorescence confocal mode, the red laser is retained, and the time-correlated single photon counting (TCSPC) technology is used to collect fluorescence lifetime data, providing data support for the rapid detection of the same type of failure in combination with the failure mechanism. The working principle and process of the system are as Figure 2 shown.

[0028] To achieve the detection of the performance of various materials and devices, a light path multiplexing structure can be used to switch the light source and detection components in the visible / short-wave infrared band, providing comprehensive monitoring information. The subsystem adopts a light path multiplexing structure design. The light paths of the laser confocal microscopy subsystem and the fluorescence lifetime subsystem are coaxial. Design advantages such as the telecentric system and various point scanning modes are also applicable to the fluorescence lifetime microscopy subsystem, better integrating various detection methods. To achieve automatic control and data processing, the host computer of the entire system integrates the control of the fluorescence lifetime microscopy subsystem and the acquisition and processing of photoluminescence fluorescence signals.

[0029] To improve the overall usability of the system and reduce the complexity for users during use, the functions and moving parts of the bright / dark field microscopy subsystem, the photoluminescence microscopy subsystem, the laser scanning confocal microscopy subsystem, and the fluorescence lifetime microscopy subsystem are integrated, and the host computer software is developed and tightly integrated with each subsystem. This software can not only achieve real-time acquisition, processing, and display of data, but also has powerful analysis functions, which can help researchers accurately detect and locate failed samples.

[0030] The control module ensures the integrity and display effect of image information through efficient image data reception and processing algorithms. The image data of the short-wave infrared imager is uncompressed and transmitted in Bulk mode using the USB 3.0 SuperSpeed protocol, ensuring the integrity of high-speed image information. Since the imaging device of the imager may contain blind pixels such as overheated pixels, as well as problems such as pixel background noise and uneven optical response rate, the control module incorporates a blind pixel compensation algorithm based on selective median filtering and a two-point non-uniform correction algorithm with temperature compensation, thus ensuring the visual effect of the image. At the same time, this module supports flexible adjustment of parameters such as the exposure time, cooling temperature, background subtraction, and non-uniform correction coefficient of the camera to meet the imaging requirements in different modes.

[0031] One advantage of this system is that it can simultaneously observe the laser spot and the bright field image. In addition to laser illumination, an extended light source can also be used to irradiate the sample, thus easily locating the area of interest. To improve the positioning accuracy of the visible light laser in the fluorescence confocal subsystem, the short-wave infrared laser spot can be used as an indicator, thanks to the coaxial light path designed for the short-wave infrared laser and the visible light laser in the system.

[0032] Another advantage of the system proposed by the present invention is the use of optical multiplexing technology. By adding point illumination and a scanning platform to a wide-field microscope, confocal detection can be achieved. In addition, the use of optical multiplexing technology eliminates the need for a pinhole and a photomultiplier tube (PMT), which are replaced by a low-noise short-wave infrared imager. In the proposed system, the centroid of the laser spot in the image can be automatically located in software, and a single pixel is regarded as a point detector, such as a PMT. Since the diameter of the pixel is as small as 25 μm, it is also equivalent to a 25-μm pinhole. Currently, the imager of the present invention can scan up to 20 points per second and uses region of interest (ROI) adjustment to improve the scanning speed and quality. However, in recent years, the development of short-wave infrared confocal microscopes for chip detection has still been relatively single, using traditional APDs as detectors, which is also because the readout speed of APDs is faster than that of InGaAs imagers.

Claims

1. Short-wave infrared light emission and fluorescence confocal microscopy system for integrated circuit inspection, characterized by: It includes a bright / dark field microscopy subsystem, a photon emission microscopy subsystem, a short-wave infrared laser scanning confocal microscopy subsystem, a fluorescence confocal microscopy subsystem, and a control module; the bright / dark field microscopy subsystem observes the sample through vertical illumination of a bright field light source or diffuse reflection of a dark field light source; The photon emission microscopy subsystem drives the integrated circuit to be tested for testing; the short-wave infrared laser scanning confocal microscopy subsystem uses short-wave infrared laser to focus on the sample, and the reflected light is captured by a deep-cooled InGaAs imager after passing through a beam splitter and a focusing lens; the laser emitted by the fluorescence confocal subsystem enters the short-wave infrared microscope objective through a transflective mirror and converges to the sample surface to realize the detection of short-wave infrared fluorescence lifetime; the control module is used to control the data acquisition and working mode switching of each subsystem, and process the acquired data to realize the determination of sample defects or failures.

2. The short-wave infrared light emission and fluorescence confocal microscopy system for integrated circuit detection according to claim 1, characterized in that: The bright / dark field microscopy subsystem includes a bright field light source, a dark field light source, a lens with a focal length of 200 mm and a lens with a focal length of 75 mm, a beam splitter, and an objective lens; the bright field light source vertically illuminates the test sample after passing through the lens with a focal length of 75 mm and the beam splitter; the dark field light source is arranged diagonally above the sample stage.

3. The short-wave infrared light emission and fluorescence confocal microscopy system for integrated circuit detection according to claim 1, characterized in that: The short-wave infrared laser scanning confocal microscopy subsystem includes a 1310nm laser, a lens with a focal length of 250mm and a lens with a focal length of 25.4mm, a beam splitter, a fast steering mirror, a scanning lens, a tube lens and a deep-cooled InGaAs imager; the telecentric system composed of the scanning lens and the tube lens ensures that the objective lens aperture is always fully illuminated when the fast steering mirror moves.

4. The short-wave infrared light emission and fluorescence confocal microscopy system for integrated circuit detection according to claim 1, characterized in that: The fluorescence confocal subsystem includes a 660nm laser, a lens with a focal length of 200mm, a lens with a focal length of 25.4mm, a dichroic mirror and part of the laser confocal optical path; the dichroic mirror is a long-wave pass type that transmits wavelengths above 980nm; the fluorescence excited by the laser focusing the sample is transmitted through the optical path, passes through the dichroic mirror, beam splitter and focusing lens with a focal length of 20.1mm, and then the fluorescence lifetime is detected by a single-photon detector.

5. The short-wave infrared light emission and fluorescence confocal microscopy system for integrated circuit detection according to claim 1, characterized in that: The deep-cooled InGaAs imager includes a water-cooling module, a multi-stage thermoelectric cooler, and an InGaAs short-wave infrared imager; the cold end of the multi-stage thermoelectric cooler is connected to the water-cooling module, and the hot end is connected to the InGaAs short-wave infrared imager; the deep-cooled InGaAs imager obtains high-contrast tomographic images and three-dimensional structures of failed devices through the coordinated work of an emission microscope, a short-wave infrared laser, and a three-dimensional displacement stage.

6. The short-wave infrared light emission and fluorescence confocal microscopy system for integrated circuit detection according to any one of claims 1 to 5, characterized in that: The system has four working modes: in the bright / dark field mode, only the wide-field light source is enabled to perform macroscopic detection of samples and locate the area of ​​interest or the failed part; in the emission microscope mode, the wide-field light source is turned off to capture the luminescent image of the failed device for precise positioning; in the laser confocal scanning mode, the wide-field light source and the short-wave infrared laser are enabled at the same time, and the wide-field light source is turned off after determining the scanning range according to the size of the failed device, and the two-dimensional high-contrast image and three-dimensional stereo image of the key components of the sample are obtained by scanning with a translation stage; in the fluorescence confocal mode, the red laser is retained, and the fluorescence lifetime data is collected using the time-correlated single photon counting technology.

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