A polarized light microscopy system and method for inspecting semiconductor light emitting chips

Abstract

The application discloses a kind of detection semiconductor light-emitting chip's polarized microscopy system and method, system includes chip excitation module, incident illumination modulation module, microscopic adjustment module, exit imaging module and control and image processing module.The application is continuously polarized by control module to incident illumination modulation module Modulation, modulated incident light is acted on light-emitting chip exit end face by microscopic system module, simultaneously using control module to adjust exit imaging module and carry out real-time image collection, obtain the polarized parameter image of exit end face by image processing module;Close incident illumination module, after using chip excitation module to excite light-emitting chip, adjust three-dimensional platform and exit imaging module by control module, real-time image collection, finally obtain the polarized parameter diagram of near-field light spot by image processing module.The application has very strong characterization ability and high sensitivity to the end face structure and near-field light spot of semiconductor light-emitting chip.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of polarization microscopy detection, and particularly relates to a polarization microscopy system and method for detecting a semiconductor light-emitting chip. BACKGROUND

[0002] With the increasing demand of semiconductor light-emitting chips in the fields of biological medicine, industrial manufacturing, aerospace and national defense, the detection of the end face structure of the semiconductor light-emitting chip and the detection of the light spot characteristics are particularly important. The quality of the semiconductor light-emitting device is largely dependent on the quality of the chip, so the detection of the semiconductor light-emitting chip is an important research content for judging the quality. The detection of the semiconductor light-emitting chip generally includes end face structure detection and light spot characteristic detection, and the structure and impurity distribution of the chip end face will affect the light spot. Since the size of the semiconductor light-emitting chip is relatively small, it is mostly micro-nano level, so the detection of the end face structure generally uses an electron scanning microscope (SEM) and an optical microscope. The resolution of the SEM is much higher than that of the traditional optical microscope, which can reach tens of nanometers, and can complete the detection of the end face structure and defects of the semiconductor light-emitting chip. However, the SEM is expensive, bulky and needs to be installed in a place without any electromagnetic and vibration interference. It is still difficult to popularize the SEM in scientific research and production at present. The optical microscope is relatively cheap, but due to the limitation of its resolution, it may not be able to clearly distinguish the small impurities and defects on the end face of the semiconductor light-emitting chip, resulting in missed detection. Therefore, how to use the optical microscope to achieve the best resolution is an important problem. At the same time, after the end face structure of the semiconductor light-emitting chip is detected, a new experimental platform needs to be built to detect the quality of the near-field light spot. The two detection systems are independent, and the close relationship between the end face structure defects and impurities and the quality of the light spot may be missed. In addition, with the continuous improvement of the CCD pixel, its measurement accuracy is also higher and higher, and the measurable wavelength range is also very wide. In the detection of the light spot of the semiconductor light-emitting chip, the CCD measurement method is usually used to directly detect the light spot in real time. In order to protect the light-sensitive surface of the CCD, an attenuating sheet is usually added to the detection system, which will increase the measurement error. SUMMARY

[0003] The application aims to provide a polarization microscopy system for detecting a semiconductor light-emitting chip.

[0004] The technical scheme for realizing the application is as follows: a polarization microscopy system for detecting a semiconductor light-emitting chip, comprising:

[0005] The chip excitation system module, the incident illumination modulation module, the microscopic adjustment module, the outgoing imaging modulation module, the control and image processing module and the three-dimensional moving platform module, the chip excitation system module comprises a stabilized current source, a temperature control system and a sample platform, the incident illumination modulation module is used for emitting linearly polarized light; the microscopic adjustment module and the outgoing imaging modulation module are arranged on the three-dimensional moving platform module, the microscopic adjustment module comprises an objective lens, a coaxial adjustment frame and a half-transmission half-reflection mirror, the coaxial adjustment frame is used for realizing the exchange of the half-transmission half-reflection mirror and an attenuating sheet, and the light passes through the objective lens and the half-transmission half-reflection mirror to enter the outgoing imaging modulation module; the outgoing imaging modulation module is used for testing linearly polarized light of different polarization angles and collecting polarized light intensity original maps of different polarization angles.

[0006] The control and image processing module is used for controlling the three-dimensional moving platform module to focus on the chip end surface position, controlling the incident illumination modulation module to obtain linearly polarized light of different polarization angles, controlling the outgoing imaging modulation module to collect polarized light intensity original maps of different polarization angles, and respectively processing the collected light intensity original maps of different polarization angles to obtain the polarization parameter images of the chip end surface structure and the near-field light spot.

[0007] Preferably, the incident illumination modulation module comprises a light source, a linear polarizer 1 and a stepping motor 1, the linear polarizer 1 is placed in the stepping motor 1, one end of the stepping motor 1 is connected with the light source, and the other end is connected with the microscopic adjustment module.

[0008] Preferably, the outgoing imaging modulation module comprises a 1 / 4 wave plate, a stepping motor 2, a linear polarizer 2, an imaging lens and a plane array CCD, the light signal carrying polarization information passes through the 1 / 4 wave plate and the linear polarizer 2, is imaged to the plane array CCD by the imaging lens, the plane array CCD is located at the focal point position of the imaging lens, and the linear polarizer 2 is placed in the stepping motor 2.

[0009] Preferably, the fast axis of the 1 / 4 wave plate in the outgoing imaging modulation module forms a 45° angle with the X axis (the 1 / 4 wave plate is located in the XY plane), when the end surface structure of the semiconductor light-emitting chip is detected, the light transmission axis of the linear polarizer 2 is along the X axis direction, when the near-field light spot is detected, the control module controls the linear polarizer 2 to rotate clockwise.

[0010] Preferably, the incident illumination modulation module is turned on when the end surface structure is detected, and the control and image processing module is used to control the stepping motor 1 to rotate the linear polarizer 1 clockwise.

[0011] Preferably, the chip excitation system module is used when the near-field light spot of the semiconductor light-emitting chip is detected after the chip end surface structure detection is completed, the current source is used to excite the semiconductor light-emitting chip, the temperature control system is used to control the temperature of the chip after excitation to be in a set range, and the control and image processing module is used to turn off the motor 1 when the near-field light spot is detected.

[0012] Preferably, the original light intensity images of different polarization angles are processed to obtain the chip end face structure polarization parameter images, and the specific method is as follows:

[0013] When detecting the polarization parameter images of the chip end face structure, the light intensity Ii collected by the CCD is specifically as follows:

[0014]

[0015] Wherein, I0 is the polarization intensity after removing the system and chip end face surface absorption, α i is the incident polarization angle, φ is the azimuth angle, and δ is the phase delay. The above formula is regarded as the function of the light intensity I i and the polarization angle α i , and the above formula is changed to:

[0016] I i = a0+ a1 sin 2a i + a2 cos 2a i

[0017] Wherein:

[0018]

[0019] The light intensity under the incident light of different polarization angles is collected, the polarization angle α i of the incident light is modulated from 0° to 180°, and the step length of the modulation is N = 180° / 18°. According to the Fourier series expansion formula, a0, a1 and a2 are obtained as follows:

[0020]

[0021] N is the modulation step number, which is a positive integer.

[0022] Three different polarization parameter images of the chip end face structure are obtained, and the depolarization intensity I dp , the phase delay δ and the azimuth angle φ are specifically as follows:

[0023]

[0024] Preferably, the original light intensity images of different polarization angles are processed to obtain the chip end face structure polarization parameter images, and the specific method is as follows:

[0025] When detecting the polarization parameter images of the near-field light spot, the light intensity I' of the polarization light intensity image of the semiconductor light emitting chip near-field light spot collected is specifically as follows:

[0026] I' = [S0+S1 cos 2θ+S2 sin 2θcos a1-S3 sin 2θsin a]

[0027] wherein, θ is the included angle between the light transmission axis of the polarizer and the horizontal axis, α1 is the included angle between the fast axis of the 1 / 4 wave plate and the horizontal axis, and α = 45°, S0, S1, S2, S3 are Stokes parameters, then the above formula is rewritten as:

[0028]

[0029] Let θ = ωt, then the above formula is specifically expressed as:

[0030]

[0031] Let s = S3, Therefore, the above formula is specifically expressed as:

[0032]

[0033] According to Fourier transform, A, B, C, D are expressed as,

[0034]

[0035] The phase retardation δ' and the azimuth angle φ' of the near-field light spot are specifically:

[0036]

[0037] The present application provides a kind of detecting semiconductor light-emitting chip polarization microscopy method, specific steps are:

[0038] Step 1: construct polarization microscopy system, in control and image processing module, input the initial parameters of stepper motor 1, including motor rotation speed, acceleration time, pause time, rotation interval angle, modulation mode;Input the moving speed, moving step, pause time, moving direction of three-dimensional moving platform;Set camera exposure time and image saving path;

[0039] Step 2: control and image processing module sends control signal, controls stepper motor 1 to drive the light transmission axis of linear polarizer 1 in incident modulation module to reach initial angle, and carries out polarization state modulation of incident light beam;Control three-dimensional moving platform to reach end face image focus point, while controlling face array CCD to collect several chip end face structure images of different polarization angles;

[0040] Step 3: close incident illumination modulation module, and remove half-mirror in microscopic adjustment module coaxial adjustment frame, replace attenuation sheet;Open the stabilized current source, control chip excitation system to excite chip, while controlling temperature control adjustment system, keep chip temperature in the set range;

[0041] Step 4: In the control and image processing module, input the initial parameters of stepper motor 2, including motor rotation speed, acceleration time, pause time, rotation interval angle, and modulation mode; maintain the position of the three-dimensional moving platform at the focal point in step 2; set the camera exposure time and image saving path;

[0042] Step 5: The control and image processing module sends a control signal to control the stepper motor 2 to drive the linear polarizer 2 in the output modulation module to the initial angle and perform polarization state modulation of the output near-field light spot; at the same time, it controls the area array CCD to acquire several near-field light spot images with different polarization angles.

[0043] Step 6: The control and image processing module processes the acquired semiconductor light-emitting chip end-face structure light intensity images and near-field spot images at different polarization angles to obtain their respective polarization parameter maps.

[0044] Compared with existing technologies, the significant advantages of this invention are as follows: Based on the principles of polarization imaging and microscopic imaging, this invention directly images and detects the end-face structure of semiconductor light-emitting chips without damaging the chip. Combining microscopic imaging and polarization imaging techniques achieves higher imaging resolution, distinguishing impurity distribution on the end-face and measuring and calculating the thickness of the metal overlay. Based on the principle of light polarization characteristics, this invention detects the near-field light spot of the semiconductor light-emitting chip, exhibiting high sensitivity to the photon state of the near-field light spot mode. It can recover the complete shape of the near-field light spot, depict its boundary, and analyze its polarization characteristics. Within the same system, this invention can achieve the detection of the semiconductor light-emitting chip end-face and its near-field light spot using the adjustment of a coaxial adjustment frame. Furthermore, the location of impurities on the end-face can determine the possible deformation of the near-field light spot, providing a significant advantage in the detection of semiconductor light-emitting chips. Attached Figure Description

[0045] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0046] Figure 1 A schematic diagram of a polarization microscopy system for detecting the structure of the emitting end face and the near-field light spot of a semiconductor light-emitting chip.

[0047] Figure 2 This is a schematic diagram of the coaxial adjustment frame structure in this invention. By directly replacing the semi-transparent mirror and the attenuator, the purpose of detecting the end-face structure of the semiconductor light-emitting chip and the near-field light spot can be achieved, respectively.

[0048] Figure 3 Images of the end face structure of a semiconductor chip after polarization microscopy modulation, along with images of end face impurities.

[0049] Figure 4The application discloses a near-field light spot image of a semiconductor chip under polarization microscope modulation and a simulated near-field light spot image. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical scheme and advantages of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the drawings.

[0051] As shown in the drawings, Figure 1 A polarization microscope system for detecting a semiconductor light-emitting chip is mainly used for detecting the impurity distribution of the end face of the semiconductor light-emitting chip and the complete shape and polarization state of the near-field light spot, and specifically comprises a chip excitation system module, an incident illumination modulation module, a microscope adjustment module, an exit imaging modulation module, a control and image processing module and a three-dimensional moving platform module. The chip excitation system module comprises a stabilized current source (1), a temperature control system (2) and a sample platform (3). The semiconductor light-emitting chip (4) is placed on the sample platform along the edge of the platform. The semiconductor light-emitting chip (4) is excited by the current source (1), and the temperature control system (2) is controlled, so that the temperature of the chip after excitation is controlled. The control and image processing module is used for controlling the three-dimensional moving platform module to focus on the position of the end face of the chip, controlling the incident illumination adjustment module to obtain linearly polarized light of different polarization angles, controlling the exit imaging modulation module to collect polarized light intensity original graphs of different polarization angles, and respectively processing the collected light intensity original graphs of different polarization angles to obtain the polarization parameter images of the end face structure and the near-field light spot of the chip. The three-dimensional moving platform is used for ensuring that the whole system is stably adjusted in space and accurately focuses on the end face of the semiconductor light-emitting chip. The microscope adjustment module comprises an objective lens (5), a coaxial adjustment frame (9) and a half-transmission half-reflection mirror (10). The linearly polarized light modulated by the incident illumination modulation module enters the end face structure of the chip through the half-transmission half-reflection mirror and the objective lens. The light signals reflected and scattered by the end face structure enter the exit imaging modulation module through the objective lens and the half-transmission half-reflection mirror.

[0052] In a further embodiment, the incident illumination modulation module comprises a light source (6), a linear polarizer 1 (7) and a stepping motor (8). The linear polarizer 1 is placed in the stepping motor. The front end of the stepping motor is connected with the light source, and the rear end is connected with the coaxial adjustment frame (9) in the microscope adjustment module, so as to ensure that they are located on the same optical axis.

[0053] Specifically, when the end face structure of the chip is detected, the light source (6) needs to be turned on, and the control module is used to control the stepping motor 1 (8) to rotate the linear polarizer 1 (7) clockwise. When the near-field light spot is detected, the light source (6) is turned off, the control module is used to turn off the stepping motor 1 (8), and the stepping motor 2 (12) in the exit imaging modulation light path is controlled.

[0054] In a further embodiment, as shown in the drawings, Figure 2As shown, the coaxial adjustment frame (9) in the fine adjustment module can simply and quickly realize the exchange of the same size half-transmission half-reflection mirror (10) and the attenuation sheet (19), effectively convert between the chip end face structure and the near field spot, and complete the detection of the semiconductor light emitting chip end face structure and the near field spot. In some embodiments, the attenuation sheet with T=0.1% is used. A long focus objective lens with a magnification of 50X and a numerical aperture of 0.8 is used.

[0055] In further embodiments, the exit imaging modulation module includes a 1 / 4 wave plate (11), a stepping motor connector (12), a linear polarizer 2 (13), an imaging lens (14), and a face array CCD (15). The light signal carrying polarization information passes through the 1 / 4 wave plate and the linear polarizer, is imaged to the face array CCD by the imaging lens, the CCD is located at the focal point position of the lens, and the linear polarizer 2 is placed in the stepping motor. When detecting the near field spot, the linear polarizer is rotated.

[0056] Specifically, the fast axis of the 1 / 4 wave plate (11) in the exit imaging modulation module is at an angle of 45° with the X axis (the 1 / 4 wave plate is located in the XY plane). When detecting the end face structure of the semiconductor light emitting chip, the light transmission axis of the linear polarizer 2 is along the X axis direction, and when detecting the near field spot, the control module controls the stepping motor 2 to rotate the linear polarizer 2 clockwise.

[0057] In further embodiments, by controlling the image processing module, when detecting the end face structure of the light emitting chip and the near field spot, the linear polarizer 1 and the linear polarizer 2 are respectively controlled to rotate at equal interval angles, and the maximum angle is 360°.

[0058] In further embodiments, the control and image processing module controls the rotation angle of the polarization plate to be equal interval according to the control program written by the related software, sets the CCD exposure time and the shooting interval time, and synchronously completes the corresponding image acquisition.

[0059] In further embodiments, the control and image processing module respectively processes the collected multiple semiconductor light emitting chip end face structure original drawings and near field spot original drawings to obtain the polarization parameter diagram of the chip end face structure and the near field spot. The polarization parameters of the end face structure include the depolarization intensity I dp , the phase delay δ, and the azimuth angle φ. The specific process is as follows:

[0060] The linear polarizer 1 is rotated to make the polarization field of the incident light from 0° to 180°, and the CCD collects the light intensity I i Specifically,

[0061]

[0062] Wherein, I0 is the polarized intensity removed system and chip end surface surface absorption, a is the incident polarization angle, φ is the azimuth angle, δ is the phase delay, and the above formula is regarded as the function between light intensity I and polarization angle a, then the above formula is changed to:

[0063] I i = a0 + a1 sin 2a i + a2 cos 2a i

[0064] Wherein:

[0065]

[0066] The polarization angle a of incident light i From 0° to 180°, the step length of modulation is N = 180° / 18°, according to the Fourier series expansion, a0, a1, a2 are represented as:

[0067]

[0068] Three different polarization parameter images of the chip end surface structure are obtained, and the depolarization intensity I dp , the phase delay δ and the azimuth angle φ are specifically:

[0069]

[0070] The polarization parameters of the near-field spot include the phase delay δ' and the azimuth angle φ', and the specific process is:

[0071] Rotating the linear polarizer 2 from 0° to 180°, the light intensity I' of the near-field spot collected by the area array CCD is specifically:

[0072] I' = [S0 + S1 cos 2θ + S2 sin 2θcos a1 - S3 sin 2θsin a1]

[0073] Wherein, θ is the included angle between the polarizer light transmission axis and the horizontal axis, a1 is the included angle between the 1 / 4 wave plate fast axis and the horizontal axis, and a = 45°, S0, S1, S2, S3 are Stokes parameters, then the above formula is rewritten as:

[0074]

[0075] Let θ = ωt, then the above formula is specifically represented as:

[0076]

[0077] Let B = S3, Therefore, the above formula is specifically represented as:

[0078]

[0079] According to Fourier transform, A, B, C, D are expressed as,

[0080]

[0081] The polarization parameters of the two different characteristics of the near-field spot of the semiconductor light-emitting chip, the phase delay δ' and the azimuth angle φ', are specifically:

[0082]

[0083] A polarization microscopic method for detecting a semiconductor light-emitting chip, the specific steps are:

[0084] Step 1: In the control and image processing module, input the initial parameters of the stepper motor 1, including the motor rotation speed, acceleration time, pause time, rotation interval angle, modulation mode; input the moving speed, moving step, pause time, moving direction of the three-dimensional moving platform; set the camera exposure time and image saving path;

[0085] Step 2: The control and image processing module sends a control signal to control the stepper motor 1 to drive the transmission axis of the linear polarizer in the incident modulation module to reach the initial angle 0°, and to modulate the polarization state of the incident light beam; control the three-dimensional moving platform to reach the clearest place (focal point) of the end surface image, and control the area array CCD to collect N chip end surface structure images with different polarization angles at the same time;

[0086] Specifically, the initial angle of the polarizer 1 in the incident light adjustment module is 0°, the adjustment interval is 18°, and the step is N=10, at this time the transmission axis of the polarizer 2 of the outgoing imaging modulation module is at an angle of 45° with the X axis in the XY plane,

[0087] The CCD collects the light intensity I i Specifically,

[0088]

[0089] Where I0 is the polarization intensity removed by the system and the chip end surface absorption, α i is the incident polarization angle, φ is the azimuth angle, and δ is the phase delay, and the above formula is regarded as the function between the light intensity I and the polarization angle α i , then the above formula is changed to:

[0090] I i =α0+α1 sin 2α i +α2 cos 2α i

[0091] Where:

[0092]

[0093] Polarization angle of incident light α i From 0° to 180°, the step length of modulation is N = 180° / 18°, according to the Fourier series expansion, it is derived that α0, α1, α2 are expressed as:

[0094]

[0095] Step 3: Turn off the incident illumination modulation module, and remove the half mirror in the coaxial adjustment frame of the microscopic adjustment module, and replace it with an attenuating sheet; turn on the stabilized current source, control the chip excitation system to excite the chip, and at the same time control the temperature control adjustment system to keep the chip temperature appropriate;

[0096] In an embodiment, taking a superluminescent diode chip (SLD) as an example, the working current is 10 mA, 20 mA, etc., and according to different working currents, different attenuating sheets with different attenuation degrees are used, and the temperature control system is adjusted to keep the chip temperature at 20℃

[0097] Step 4: In the control and image processing module, input the initial parameters of the stepper motor 2, including the motor rotation speed, acceleration time, pause time, rotation interval angle, modulation mode; keep the three-dimensional moving platform position at the focal point in step 2; set the camera exposure time and image saving path.

[0098] Step 5: The control and image processing module sends a control signal to control the stepper motor 2 to drive the transmission axis of the linear polarizer in the incident modulation module to the initial angle, and to perform polarization state modulation of the outgoing near-field spot; at the same time, control the area array CCD to collect N near-field spot images with different polarization angles;

[0099] Specifically, the initial angle of the polarizer 2 in the outgoing imaging adjustment module is calibrated to 0°, the adjustment interval is 18°, and the step length is N = 10, and the near-field spot of the SLD chip is detected,

[0100] The light intensity I' of the near-field spot collected by the area array CCD is specifically:

[0101] I' = [S0 + S1 cos 2θ + S2 sin 2θcosα1 - S3 sin 2θsinα1]

[0102] Where θ is the angle between the transmission axis of the polarizer and the horizontal axis, α1 is the angle between the fast axis of the 1 / 4 wave plate and the horizontal axis, and α1 = 45°, S0, S1, S2, S3 are Stokes parameters, then the above formula is rewritten as:

[0103]

[0104] Let θ = ωt, then the above formula is specifically expressed as:

[0105]

[0106] Let B = S3, Therefore, the above formula is specifically expressed as:

[0107]

[0108] According to Fourier transform, A, B, C and D are represented as,

[0109]

[0110] Step 6: Control and image processing module respectively processes the collected semiconductor light-emitting chip end face structure light intensity images and near-field spot images of different polarization angles to obtain their respective polarization parameter maps;

[0111] In further embodiments, the polarization parameters of three different features of the end face structure of the SLD and the polarization parameters of two different features of the near-field spot are obtained, specifically,

[0112] The three different polarization parameter images of the SLD end face structure are depolarization intensity I dp , phase delay δ and azimuth angle φ, specifically,

[0113]

[0114] The two different polarization parameters of the SLD near-field spot are phase delay δ' and azimuth angle φ', specifically,

[0115]

[0116] The present application is based on the principles of polarization imaging and microscopic imaging, directly images and detects the end face structure of the semiconductor light-emitting chip without damaging the chip, combines microscopic imaging technology and polarization imaging technology to obtain higher imaging resolution, resolves the impurity distribution of the end face, and measures and calculates the thickness of the metal cover layer; the present application detects the near-field spot of the semiconductor light-emitting chip based on the principle of polarization characteristics of light, is very sensitive to the photon state of the near-field spot mode, can restore the complete shape of the near-field spot, delineate the boundary of the near-field spot and analyze its polarization characteristics; the present application can realize the detection of the end face of the semiconductor light-emitting chip and the detection of its near-field spot in the same system by adjusting the coaxial adjusting frame, and the position of the end face impurity can be used to judge the possible deformation of the near-field spot, which has great advantages in the detection of semiconductor light-emitting chips, can quickly, accurately and low-cost detect semiconductor light-emitting chips.

[0117] The above descriptions are only the preferable embodiments of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of the changes or replacements within the technical scope disclosed by the present application, which should be covered in the protection scope of the present application.

[0118] It should be understood that, in the description of the example embodiments of the present application above, various features of the present application are sometimes described in a single embodiment or with reference to a single drawing figure, for the purpose of brevity. However, this description is not to be interpreted in the limiting sense. Rather, the description is intended to cover all possible combinations that can be made with the various features described throughout this specification.

[0119] It should be understood that the modules, units, components, etc. included in the apparatus of one embodiment of the present application can be adaptively changed to be arranged in a device different from the embodiment. Different modules, units, or components included in the apparatus of the embodiment can be combined into one module, unit, or component, or divided into multiple sub-modules, sub-units, or sub-components.

Claims

1. A polarized light microscopy system for inspecting a semiconductor light emitting chip, characterized by It includes a chip excitation system module, an incident illumination modulation module, a microscopic adjustment module, an exit imaging modulation module, a control and image processing module and a three-dimensional mobile platform module, the chip excitation system module includes a stabilized current source (1), a temperature control system (2) and a carrier platform (3), the incident illumination modulation module is used for emitting linearly polarized light; the microscopic adjustment module and the exit imaging modulation module are arranged on the three-dimensional mobile platform module, the microscopic adjustment module includes an objective lens (5), a coaxial adjustment frame (9) and a half-transmission half-reflection mirror (10), the coaxial adjustment frame (9) is used for realizing the exchange of the half-transmission half-reflection mirror (10) and an attenuating sheet (19), the light passes through the objective lens (5), the half-transmission half-reflection mirror (10) and enters the exit imaging modulation module; the exit imaging modulation module is used for testing linearly polarized light of different polarization angles and collecting polarized light intensity original maps of different polarization angles; the control and image processing module is used for controlling the three-dimensional mobile platform module to focus on the chip end surface position, controlling the incident illumination modulation module to obtain linearly polarized light of different polarization angles, controlling the exit imaging modulation module to collect polarized light intensity original maps of different polarization angles, and respectively processing the collected light intensity original maps of different polarization angles to obtain polarization parameter images of the chip end surface structure and the near-field light spot; the incident illumination modulation module includes a light source (6), a linear polarizer 1 (7) and a stepping motor 1 (8), the linear polarizer 1 (7) is placed in the stepping motor 1 (8), one end of the stepping motor 1 (8) is connected with the light source, and the other end is connected with the microscopic adjustment module; the exit imaging modulation module includes a 1 / 4 wave plate (11), a stepping motor 2 (12), a linear polarizer 2 (13), an imaging lens (14) and a plane array CCD (15), the light signal carrying polarization information passes through the 1 / 4 wave plate and the linear polarizer, is imaged to the plane array CCD (15) by the imaging lens (14), and the plane array CCD (15) is located at a focal point position of the imaging lens (14). The fast axis of the 1 / 4 wave plate (11) in the exit imaging modulation module is at an angle of 45° with the X axis, when the end surface structure of the semiconductor light-emitting chip is detected, the light transmission axis of the linear polarizer 2 (13) is along the X axis direction, when the near-field light spot is detected, the control module controls the linear polarizer 2 (13) to rotate clockwise.

2. The polarized light microscopy system for inspecting a semiconductor light emitting chip according to claim 1, characterized in that The incident illumination modulation module is turned on when the end surface structure is detected, and the control and image processing module is used to control the stepping motor 1 (8) to rotate the linear polarizer 1 (7) clockwise.

3. The polarized light microscopy system for inspecting a semiconductor light emitting chip according to claim 1 or 2, characterized in that The chip excitation system module is used after the chip end surface structure detection is completed, the semiconductor light-emitting chip is excited by using the current source, the temperature of the chip after excitation is controlled in a set range by the temperature control system, and the near-field light spot is detected by using the control and image processing module to turn off the stepping motor 1 (8).

4. The polarized light microscopy system for inspecting a semiconductor light emitting chip according to claim 1 or 2, characterized in that The specific method for processing the collected light intensity original maps of different polarization angles to obtain the polarization parameter images of the chip end surface structure is as follows:

5. The polarized light microscopy system for inspecting a semiconductor light emitting chip according to claim 1, wherein wherein: When detecting the polarized parameter image of the end face structure of the chip, the light intensity collected by the CCD Specifically where to remove the polarization intensity absorbed by the system and the chip end surface, for the incident polarization angle, is the azimuth angle, is the phase delay, and considering the above equation as a function of the light intensity and the polarization angle , the above equation is modified as: ​ The light intensity under different polarization angle incident light is collected, the polarization angle of the incident light is From 0° to 180°, the step length of the modulation is N=180° / 18°, according to the Fourier series expansion formula, it is derived that 、 、 is represented as: for modulation step size, is a positive integer; Three different polarization parameter images of the chip facet structure are obtained, the depolarization strength , the phase delay and the azimuth are obtained, in particular: 。 6. The polarized light microscopy system for inspecting a semiconductor light emitting chip according to claim 1, wherein The specific method for obtaining the near-field light spot polarization parameter image by processing the collected light intensity original images of different polarization angles is as follows: When detecting the polarized parameter image of the near-field light spot, the light intensity of the polarized light intensity image of the near-field light spot of the semiconductor light-emitting chip collected Specifically: wherein is the angle between the polarizer pass axis and the horizontal axis, is the angle between the 1 / 4 waveplate fast axis and the horizontal axis, and = 45°, , , , is the Stokes parameter, then the above equation is rewritten as: Let The above equation is specifically represented as: Let , so the above formula is specifically expressed as: According to Fourier transform, A, B, C and D are represented as follows, Phase delay of near-field spot and azimuth Specifically:

7. A polarized light microscopy method of inspecting a semiconductor light emitting chip, characterized by, The specific steps are as follows: Step 1: constructing the polarization microscope system as claimed in any one of claims 1-5, inputting the initial parameters of the stepper motor 1 in the control and image processing module, including the motor rotation speed, acceleration time, pause time, rotation interval angle, modulation mode; inputting the moving speed, moving step, pause time and moving direction of the three-dimensional moving platform; setting the camera exposure time and image saving path; Step 2: the control and image processing module sends a control signal to control the stepper motor 1 to drive the transmission axis of the linear polarizer 1 in the incident modulation module to reach the initial angle, and to modulate the polarization state of the incident light beam; the three-dimensional moving platform is controlled to reach the end face image focal point, and the surface array CCD is controlled to collect N chip end face structure images of different polarization angles; Step 3: the incident illumination modulation module is turned off, and the half-transmission half-reflection mirror in the coaxial adjustment frame of the microscope adjustment module is removed and replaced with an attenuation sheet; the constant current source is turned on, the chip excitation system is controlled to excite the chip, and the temperature control adjustment system is controlled to keep the chip temperature in the set range; Step 4: in the control and image processing module, input the initial parameters of the stepper motor 2, including the motor rotation speed, acceleration time, pause time, rotation interval angle, modulation mode; keep the three-dimensional moving platform position at the focal point in step 2; set the camera exposure time and image saving path; Step 5: the control and image processing module sends a control signal to control the stepper motor 2 to drive the linear polarizer 2 in the exit modulation module to reach the initial angle, and to modulate the polarization state of the exit near-field light spot; at the same time, the surface array CCD is controlled to collect N near-field light spot images of different polarization angles; Step 6: the control and image processing module processes the collected semiconductor light-emitting chip end face structure light intensity images and near-field light spot images of different polarization angles respectively to obtain their respective polarization parameter images.

8. The polarized light microscopy method of inspecting a semiconductor light emitting chip according to claim 7, characterized by, The specific method for obtaining the chip end face structure and near-field light spot polarization parameter images by processing the collected light intensity original images of different polarization angles is as follows: When detecting the polarized parameter image of the end face structure of the chip, the light intensity collected by the CCD Specifically where is the polarization intensity absorbed by the system and the chip end surface, is the incident polarization angle, is the azimuthal angle, is the phase delay, and considering the above equation as a function of the light intensity and the polarization angle the above equation becomes: Wherein: Collect the light intensity under different polarization angle of incident light, the polarization angle of incident light From 0° to 180°, the step length of modulation is N = 180° / 18°, according to the Fourier series expansion, it is derived that 、 、 It is expressed as: Three different polarimetric images of the chip facet structure are obtained, the depolarization strength , the phase delay and the azimuth angle, in particular: When detecting the polarized parameter image of the near-field light spot, the light intensity of the polarized light intensity image of the near-field light spot of the semiconductor light-emitting chip collected Specifically: wherein is the angle between the polarizer pass axis and the horizontal axis, is the angle between the 1 / 4 waveplate fast axis and the horizontal axis, and = 45°, , , , is the Stokes parameter, then the above equation is rewritten as: Let The above equation is specifically represented as: Let , so the above formula is specifically expressed as: According to Fourier transform, A, B, C and D are represented as follows, Phase delay of near-field spot and azimuth Specifically: 。

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