Dual-path multi-angle optical fiber probe pulsed laser irradiation simulation system

Abstract

The application discloses a kind of double optical path multi-angle optical fiber probe pulse laser irradiation simulation systems, including pulse laser generation device, optical path beam splitting device, light splitting link component, optical fiber probe component, sample bearing mechanism, probe adjusting mechanism and electrical detection device, wherein optical path beam splitting device is divided into two roads by pulse laser, and each road independently sets power adjusting unit and power monitoring unit;Two optical fiber probes are aligned to the same target point in the unified coordinate system, and the incident angle and the azimuth angle are continuously adjustable;Sample bearing mechanism is configured with hollow light window, and supports front, back and inclined angle incidence;Electrical detection device synchronously acquires device response.This application solves the problem that existing platform is difficult to realize double-beam multi-angle incidence on the same target point, independent calibration and timing calibration of branch power, can obtain characteristic data of device single event effect and its synergistic effect in angle-power-timing three-dimensional parameter space, and improves test accuracy, repeatability and comparability.

Description

Technical Field

[0001] This invention relates to the field of semiconductor device irradiation and reliability testing technology, specifically to a dual-path, multi-angle fiber optic probe pulsed laser irradiation simulation system for studying the Single Event Effect (SEE) and its synergistic effects. This system is primarily used for evaluating the radiation resistance of semiconductor devices under space radiation environments, particularly for quantitative characterization and synergistic effect research on the single-event transient response, angular sensitivity, and threshold characteristics of devices under complex irradiation conditions such as multi-angle, dual-beam timing, and path coupling. Background Technology

[0002] In aerospace, nuclear energy applications, and high-energy physics experiments, semiconductor devices need to operate stably for extended periods in complex radiation environments. High-energy particles in the space radiation environment can induce single-event effects within semiconductor devices, including various failure modes such as single-event upset (SEU), single-event transient (SET), and single-event lock-in (SEL), severely impacting device reliability and safety. Therefore, evaluating the radiation resistance of semiconductor devices is a crucial step in ensuring the success of space missions. Among numerous radiation resistance evaluation methods, laser simulation of single-event effects, with its advantages of non-destructiveness, repeatability, high spatiotemporal resolution, and low cost, has become an important means to replace or supplement traditional particle beam experiments.

[0003] The basic principle of laser-simulated surface electro-optical emission (SEE) is to use nanosecond or picosecond pulsed lasers to generate particle-like transient charge deposition in the sensitive area of ​​a device, and then characterize its radiation resistance by measuring the device's electrical response. Currently, research institutions both domestically and internationally have conducted extensive related work. Institutions such as the U.S. Naval Research Laboratory, NASA Goddard Space Flight Center, Sandia National Laboratories, and CERN, as well as domestic units such as the National Space Science Center of the Chinese Academy of Sciences, the China Academy of Engineering Physics, the Northwest Institute of Nuclear Technology, and the University of Electronic Science and Technology of China, have accumulated rich technical experience in laser-simulated SEE. Existing laser simulation platforms mainly employ free-space microscopy focusing or fiber optic near-field irradiation, which can, to a certain extent, characterize the SET / SEU transient response, analyze angular sensitivity, and measure threshold values ​​of devices.

[0004] However, single-particle triggering in real-world applications is not an isolated event. Multiple factors, such as incident angle, incident surface, power density, and arrival time, often interact, leading to a nonlinear superposition of synergistic phenomena in the response of the device under test. Existing laser simulation platforms have the following limitations: First, most platforms primarily use single-source or time-division serial testing, making it difficult to achieve synchronous, alternating, or partially overlapping illumination of two beams at multiple angles within the same coordinate system and target point, thus failing to realistically simulate multi-particle synergistic effects. Second, angle and orientation adjustments are mostly discrete or uncalibrated, limiting experimental repeatability and hindering quantitative studies of angle dependence. Third, the two optical power streams lack online power calibration capabilities for independent attenuation and separate sampling, resulting in insufficient accuracy and traceability in power ratio settings. Furthermore, optical path and timing calibration capabilities are lacking, making it impossible to precisely control the arrival time difference of the two laser beams. Finally, there is limited support for back-illuminated and tilted incident structures, and the relative relationship between the two laser beams and the target point is prone to drift when the sample moves. The aforementioned factors collectively restrict the quantitative research and reproducible comparison of laser simulation SEE technology in synergistic scenarios, making it difficult to meet the needs of research on the synergistic effect laws of semiconductor devices. Summary of the Invention

[0005] To address the shortcomings of existing laser simulation single-event effect platforms, such as difficulty in achieving dual-beam multi-angle incidence at the same target point, independent setting and real-time calibration of two power paths, and insufficient optical path and timing calibration, this invention provides a dual-optical-path multi-angle fiber probe pulsed laser irradiation simulation system. By combining a dual-optical-path beam splitting design with a multi-angle probe adjustment mechanism, a controllable, calibrable, and reproducible dual-beam synergistic irradiation field is constructed in a unified coordinate system. This enables quantitative research on the single-event effect and its synergistic effect of semiconductor devices under complex irradiation conditions, providing a more comprehensive and accurate experimental means for evaluating the radiation resistance performance of semiconductor devices.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A dual-path, multi-angle fiber optic probe pulsed laser irradiation simulation system includes:

[0008] A pulsed laser generating device, used to generate a pulsed laser beam with set parameters;

[0009] An optical beam splitter is connected to the output end of the pulsed laser generating device and is used to split the pulsed laser beam into a first optical path and a second optical path.

[0010] The beam splitting link components are respectively set on the first optical path and the second optical path, including a power adjustment unit for independently adjusting the laser power of each optical path and a power monitoring unit for real-time detection and calibration of the laser power of each optical path.

[0011] The fiber optic probe assembly includes a first fiber optic probe connected to the end of a first optical path and a second fiber optic probe connected to the end of a second optical path;

[0012] A sample carrier mechanism is used to place the sample of the semiconductor device under test. The sample carrier mechanism is provided with a hollow light-transmitting window to provide an incident channel for the fiber optic probe assembly.

[0013] The probe adjustment mechanism is used to clamp and adjust the spatial position and angle of the first and second fiber optic probes, so that the two fiber optic probes are aligned with the same target point of the semiconductor device under test in a unified coordinate system and the incident angle and azimuth angle are continuously adjustable.

[0014] An electrical detection device is used to collect the electrical response of a semiconductor device under test under laser irradiation, including an electrical probe electrically connected to the semiconductor device under test and a signal acquisition unit electrically connected to the electrical probe.

[0015] The first and second fiber optic probes, through spatial positioning and timing coordination, form a dual-path multi-angle irradiation field in the working area of ​​the semiconductor device under test, which can be opposed or opposite in direction.

[0016] Specifically, the pulsed laser generating device includes a pulsed fiber laser and its driving control unit. The center wavelength range of the pulsed fiber laser covers the absorption band of semiconductor materials, the pulse width range is from nanosecond to picosecond, the repetition frequency is adjustable, and the single pulse energy is controllable.

[0017] Specifically, the optical path beam splitting device includes an optical fiber isolator and an optical fiber splitter. The optical fiber isolator is connected to the output end of the pulsed laser generating device to suppress backlighting. The optical fiber splitter is connected to the output end of the optical fiber isolator to split the pulsed laser beam into a first optical path and a second optical path according to a preset ratio, so as to ensure the homogeneity of the two lasers and facilitate timing synchronization and power balance. The preset ratio is preferably 1:1.

[0018] Specifically, the power adjustment unit is a manually adjustable fiber optic attenuator with an adjustable attenuation range of at least 0dB to 30dB, used to independently adjust the laser power of each optical path and achieve differentiated power settings for the two paths; the power monitoring unit includes a fiber optic sampling coupler and an energy meter, wherein the main channel coupling ratio of the fiber optic sampling coupler is ≥99% and the sampling channel coupling ratio is ≤1%, and the energy meter is connected to the sampling channel to read the sampling power of each optical path in real time and perform power calibration accordingly, thereby improving the accuracy of power ratio setting and the repeatability of the experiment.

[0019] Specifically, the fiber optic link lengths of the first and second optical paths are equal or calibrated to achieve synchronous arrival of the two pulsed laser beams at the target point or a set relative delay. Thus, by controlling the difference in fiber optic link lengths, synchronous, alternating, or partially overlapping irradiation of the two laser beams can be achieved, meeting the needs of synergistic effect research under different timing conditions.

[0020] Specifically, the numerical aperture range of the first and second fiber probes is 0.1 to 0.5, the core diameter range is from single-mode to multi-mode fiber specifications, and the working distance is adjustable to adapt to the irradiation requirements of sensitive areas of devices of different sizes, so that the laser can be focused on the device surface in a near-field manner to achieve high-precision fixed-point irradiation.

[0021] Specifically, the signal acquisition unit is configured as an oscilloscope, which has a trigger interface connected to the trigger output of the pulsed laser generating device to establish a unified time reference and synchronously acquire the steady-state and transient electrical responses of the semiconductor device under test. This facilitates the accurate acquisition of the electrical response waveform of the device under laser irradiation, providing data support for SEE characteristic analysis.

[0022] Specifically, the probe adjustment mechanism includes a probe stage and a universal probe clamp. Multiple universal probe clamps are configured to hold a first fiber optic probe, a second fiber optic probe, and an electrical probe, respectively. Each universal probe clamp is equipped with three displacement adjustment knobs with scales corresponding to the X / Y / Z directions and one angle control knob with scales. Each knob has a locking structure to achieve repeated positioning. The angle control knob can rotate 360°.

[0023] Specifically, the probe station is configured as a double-sided probe station, on which an upper support plate and a lower support plate are arranged vertically. A notch is opened at the center of the upper and lower support plates to facilitate the coaxial arrangement of the sample support mechanism. The first optical fiber probe is placed on the upper support plate and the second optical fiber probe is placed on the lower support plate, so that the second optical fiber probe can approach or pass through the hollow light-transmitting window to achieve back or tilted incident under non-zero incident angle conditions. This allows the two optical fiber probes to be aligned with the same target point of the semiconductor device under test in a unified coordinate system, and realizes continuous adjustment of incident angle and azimuth angle, ensuring high-precision positioning and long-term stability of the experiment.

[0024] Specifically, the sample support mechanism includes a sample stage for placing the semiconductor device sample under test and a manual XYZ displacement stage for supporting the sample stage. The manual XYZ displacement stage shares the same base and coordinate system with the probe adjustment mechanism to ensure that the relative angles of the two optical paths remain consistent with the target point during movement or scanning. Preferably, the sample stage is a hollowed-out sample stage with a hollowed-out light-transmitting window positioned on it, providing ample incident space for the fiber optic probe below while ensuring stable sample placement.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) This invention can reproduce multi-directional, synchronous, alternating or partially overlapping excitation scenarios in the actual radiation environment by using dual optical paths and multi-angle irradiation at the same target point in the same coordinate system. This breaks through the applicability limitations of the existing single-beam platform in the study of synergistic effects, and can complete dual-beam irradiation testing in a single experiment. Compared with traditional time-division serial testing, the experimental efficiency is significantly improved, while avoiding device state change errors caused by time-division testing.

[0027] (2) The present invention adopts a link design of independent attenuation and sampling measurement of the two lasers and uses an energy meter to achieve real-time reading, thereby realizing independent setting, online calibration and full traceability of the power of the two lasers, which significantly improves the accuracy and repeatability of power ratio and energy density setting.

[0028] (3) The present invention, through the combined design of a universal probe fixture, a double-sided probe stage and a manual XYZ displacement stage plus a hollow sample support, ensures the overlap of target points and the consistency of angles of the two laser beams during movement or scanning, improves long-term stability and repeatability, and makes the experimental results of different batches comparable.

[0029] (4) Based on an equal-length or calibrated fiber optic link and an oscilloscope trigger reference, the device can acquire electrical responses under synchronous, sequential and partially overlapping timing conditions, which facilitates the construction of an angle-power-timing three-dimensional response surface and quantitatively reveals the laws of cooperative gain / suppression and threshold changes.

[0030] (5) The device of the present invention does not rely on an electronically controlled motion system. It achieves continuous adjustment of attitude and position with mechanical knobs. It has a compact structure, is easy to maintain and convenient to deploy. It is suitable for conducting standardized and reproducible synergistic effect tests on various types of semiconductor devices, reducing equipment costs and maintenance difficulties. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention.

[0032] Figure 2This is a partial structural diagram of an embodiment of the present invention.

[0033] Figure 3 This is a schematic diagram of the structure of the universal probe fixture in an embodiment of the present invention.

[0034] Figure 4 This is a structural block diagram of an embodiment of the present invention.

[0035] Figure 5 The transient peak current variation curves of the device under different laser incident angles are shown in the embodiment of the present invention.

[0036] Figure 6 The curves showing the change in charge collected by the device under different laser incident angles are shown in the embodiment of the present invention.

[0037] In the above figures, the component names corresponding to the reference numerals are as follows:

[0038] 1-Pulsed fiber laser, 2-Power supply, 3-Fiber optic isolator, 4-Fiber optic splitter, 5-Manually adjustable fiber optic attenuator, 6-Fiber optic sampling coupler, 7-Energy meter, 8-Manual XYZ displacement stage, 9-Oscilloscope, 10-Probe stage, 11-Universal probe holder, 12-Fiber optic probe assembly, 13-Electrical probe, 14-X-axis displacement adjustment knob, 15-Y-axis displacement adjustment knob, 16-Z-axis displacement adjustment knob, 17-Displacement scale, 18-Angle control knob, 19-Lockable movable joint, 20-Miniature digital inclinometer, 21-Sample stage, 22-Sample. Detailed Implementation

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments. The embodiments of the present invention include, but are not limited to, the following embodiments.

[0040] Example

[0041] like Figures 1 to 6 As shown, the dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system mainly consists of four functional modules: pulsed laser and beam splitting attenuation sampling module, mechanism platform module, detection module, and control and safety module. The structure and working principle of each module are explained below.

[0042] The pulsed laser and beam splitting attenuation sampling module is used to generate pulsed lasers with set parameters and to achieve independent power setting and online calibration on the two optical paths after beam splitting. It involves a pulsed laser generating device, an optical path beam splitting device, a beam splitting link assembly, and an optical fiber probe assembly. The pulsed laser generating device generates a pulsed laser beam with set parameters, including a pulsed fiber laser 1 and its drive control unit. The center wavelength range of the pulsed fiber laser covers the absorption band of semiconductor materials, the pulse width ranges from nanoseconds to picoseconds, the repetition frequency is adjustable, and the single pulse energy is controllable. The optical beam splitting device is used to split the pulsed laser beam into a first optical path and a second optical path. Specifically, it includes an optical fiber isolator 3 and an optical fiber splitter 4. The optical fiber isolator 3 is connected to the output end of the pulsed fiber laser 1 to suppress backlight and prevent reflected light from returning to the laser, causing output instability or device damage. The optical fiber splitter 4 is connected to the output end of the optical fiber isolator 3. A 1×2 optical fiber splitter with a 50:50 splitting ratio can be used to split the pulsed laser beam into the first optical path and the second optical path according to a preset 1:1 ratio to ensure the homogeneity of the two lasers and facilitate timing synchronization and power balance.

[0043] An optical link assembly is set up on the first and second optical paths respectively. Each optical link assembly includes a power adjustment unit for independently adjusting the laser power of each optical path and a power monitoring unit for real-time detection and calibration of the laser power of each optical path. In this embodiment, the power adjustment unit uses a manually adjustable fiber optic attenuator 5, configured with an adjustable attenuation range of 0dB to 30dB, to independently adjust the laser power of each optical path, realize differentiated settings of the two paths' power, and meet the requirements for synergistic effect testing under different power ratio conditions. For example, the power of the first optical path can be set to twice the power of the second optical path to study the synergistic response characteristics under asymmetric power conditions. The power monitoring unit includes a fiber optic sampling coupler 6 and an energy meter 7. The fiber optic sampling coupler 6 is connected to the output of a manually adjustable fiber optic attenuator 5. A 1×2 fiber optic sampling coupler with a 99:1 ratio can be selected, with a coupling ratio of 99% for the main channel and 1% for the sampling channel. Neglecting insertion loss, the power of the main channel is approximately 99 times the power of the sampling channel. Considering the insertion loss of connectors and devices, this can be corrected by pre-calibrating the transmission coefficient to improve the accuracy of power calibration. The energy meter 7 is connected to the sampling channel of the fiber optic sampling coupler 6 via a fiber optic patch cord to read the sampling power of the corresponding optical path in real time. The power of the main channel can be calculated based on the reading of the energy meter, thereby realizing online detection and calibration of the power of the two optical paths.

[0044] The main channels of the two-way fiber sampling couplers 6 continue to connect to the fiber probe assembly 12. The fiber probe assembly specifically includes a first fiber probe connected to the end of the first optical path and a second fiber probe connected to the end of the second optical path. Specifically, the numerical aperture range of the first and second fiber probes is 0.1–0.5, the core diameter range is from single-mode to multi-mode fiber, and the working distance is adjustable to adapt to the irradiation requirements of sensitive areas of devices of different sizes, enabling the laser to be focused onto the device surface in a near-field manner, achieving high-precision point irradiation.

[0045] To achieve higher timing consistency, the two fiber optic links are preferably designed to be of equal length, or the length can be finely adjusted by reserving fiber optic disks, so that the two laser beams can arrive at the target point synchronously or with a set relative delay when needed. By controlling the difference in the length of the fiber optic links, the synchronous, alternating or partially overlapping irradiation of the two laser beams can be achieved, meeting the needs of synergistic effect research under different timing conditions.

[0046] The aforementioned beam splitting attenuation sampling module can be integrated and installed within a shaded space to reduce ambient light interference and improve operational safety. Fiber optic connections utilize standard interfaces such as FC / PC or FC / APC to minimize return light and insertion loss. The configured power supply 2 provides the necessary DC power to the pulsed fiber laser 1 and other active devices.

[0047] The mechanism platform module is used to realize the opposing or opposite incident and same target point alignment of two laser beams in a unified coordinate system, and provides spatial conditions for front, back, or tilted incident. It involves a sample carrying mechanism and a probe adjustment mechanism. The sample carrying mechanism includes a sample stage 21 for placing the semiconductor device sample under test and a manual XYZ displacement stage 8 for supporting the sample stage. The manual XYZ displacement stage 8 is stably placed on the base and shares a coordinate system with the probe adjustment mechanism. The sample stage 21 is stably placed on its upper movable end, which facilitates the overall movement and adjustment of the sample under test. The sample stage 21 is a hollow sample stage with a hollow light-transmitting window. While ensuring the stable placement of the sample, it provides sufficient incident space for the fiber optic probe assembly, especially providing a channel for the fiber optic probe below to approach or pass through the sample stage under non-zero incident angle conditions.

[0048] The probe adjustment mechanism is used to clamp and adjust the spatial position and angle of the first and second fiber optic probes, so that the two fiber optic probes are aligned with the same target point of the semiconductor device under test in a unified coordinate system and the incident angle and azimuth angle are continuously adjustable. Specifically, the probe adjustment mechanism includes a probe stage 10 and a universal probe clamp 11. The probe stage 10 is configured as a double-sided probe stage, on which an upper support plate and a lower support plate are arranged vertically. A notch is opened at the center of the upper and lower support plates to facilitate the coaxial arrangement of the sample carrying mechanism. The probe stage and the manual XYZ displacement stage share the same base to achieve the unification of the coordinate system, thereby ensuring that the relative relationship between the two laser beams and the target point remains consistent during movement or scanning. Multiple universal probe clamps 11 are configured to clamp the first fiber optic probe, the second fiber optic probe, and the electrical probe 13, respectively. In this embodiment, four universal probe clamps are configured, two of which clamp the first and second fiber optic probes respectively, and the other two clamp the two electrical probes respectively. Each gimbaled probe holder is equipped with an X-axis displacement adjustment knob 14, a Y-axis displacement adjustment knob 15, a Z-axis displacement adjustment knob 16, an angle control knob 18 with graduations for adjusting the horizontal angle, a lockable movable joint 19, and a miniature digital inclinometer 20. All three displacement adjustment knobs have displacement graduations 17, and each knob has a locking mechanism for repeatable positioning. The angle control knob 18 allows for continuous adjustment of the azimuth angle from 0 to 360° within the sample plane, and can be preset and locked, or unlocked at any time for smooth switching between different azimuths. The lockable movable joint 19 is used for continuous adjustment of the pitch angle relative to the sample normal, and works in conjunction with the miniature digital inclinometer 20 for real-time reading and calibration. When changes in azimuth or pitch cause spot shift, the manual XYZ displacement stage 8 and the three displacement adjustment knobs compensate for the displacement to maintain the same target point. The first fiber optic probe is mounted on the upper support plate via a universal probe clamp, and the second fiber optic probe is mounted on the lower support plate via a universal probe clamp. This allows the second fiber optic probe to approach or pass through the hollowed-out sample stage plane through the hollowed-out light transmission window under non-zero incident angle conditions to achieve back-side or tilted incident, thereby realizing continuous adjustment of the incident angle and azimuth angle, ensuring high-precision positioning and long-term stability of the experiment.

[0049] In use, the sample 22 to be tested is first placed on the sample stage 21. The target position is determined by microscopic observation or coaxial illumination. Then, the upper and lower fiber optic probes in the fiber optic probe assembly are adjusted sequentially using the universal probe holder to align with the target from above and below, respectively. Finally, the displacement and angle are locked. After alignment, the two fiber optic probes are aligned with the same target in a unified coordinate system. The incident angle and azimuth angle can be continuously adjusted according to experimental requirements. The above process, through the combined operation of "continuously adjustable azimuth angle + continuously adjustable elevation angle + XYZ displacement compensation", allows for rapid switching from normal incidence to any tilt angle and any azimuth incident direction within a unified coordinate system without changing the fixture or rebuilding the optical path.

[0050] The detection module is used to acquire the electrical response of the semiconductor device under test (DUT) under laser irradiation in real time, and involves an electrical detection device. The electrical detection device includes an electrical probe 13 electrically connected to the DUT, and a signal acquisition unit electrically connected to the electrical probe. Two electrical probes 13 are configured, and their tips form reliable electrical contact with the pads of key nodes (such as power supply terminals and output terminals) of the DUT, thereby leading the corresponding electrical signals to the signal acquisition unit. The signal acquisition unit is configured as an oscilloscope 9, used to record the electrical response waveform of the DUT. The oscilloscope bandwidth and sampling rate are configured according to the pulse width and the device response time constant. For nanosecond-level pulsed laser testing, the oscilloscope bandwidth should be no less than 1 GHz, and the sampling rate should be no less than 5 Gsa / s. The oscilloscope is equipped with a trigger interface for capturing parameters such as peak / integral current, rise time, and recovery time. The trigger interface is connected to the trigger output of the pulsed fiber laser to establish a unified time reference and synchronously acquire the steady-state and transient electrical responses of the semiconductor device under test. This facilitates the accurate acquisition of the electrical response waveform of the device under laser irradiation, providing data support for SEE characteristic analysis.

[0051] The control and safety module is used to establish a time reference, provide power, and ensure operational safety. In this embodiment, power supply 2 provides the required DC power to the system; the external trigger input of oscilloscope 9 is connected to the trigger output or synchronization branch of pulsed fiber laser 1 to establish a unified time reference and realize the switching of timing conditions such as synchronization, alternation, or partial overlap; to improve safety and immunity, a light-shielding / shielding shell can be installed around the device if necessary to reduce ambient light and electromagnetic interference.

[0052] The test procedure for SEE synergistic effect testing using a dual-path multi-angle fiber optic probe pulsed laser irradiation simulation system is as follows:

[0053] Step 1: System Initialization and Power Calibration. Turn on the pulsed fiber laser, power meter, and oscilloscope, and allow them to warm up to operating status. Set the laser output parameters (center wavelength, pulse width, repetition frequency, single pulse energy) to output a continuous pulse sequence. Read the readings from both power meters, and adjust the power of each optical path to the set value using the manually adjustable fiber optic attenuator. Record the current attenuator scale and power meter reading as the power calibration reference.

[0054] Step 2: Sample Mounting and Target Alignment. Place the semiconductor device sample under test on the perforated sample holder and determine the target location using microscopic observation. Adjust the universal probe clamp on the upper support plate to align the upper first fiber optic probe with the target. Observing from the back of the sample, adjust the universal probe clamp on the lower support plate to align the lower second fiber optic probe with the same target. Set the incident angle and azimuth angle of the two fiber optic probes according to experimental requirements and tighten all adjustment knobs. Simultaneously, adjust the two electrical probes to establish reliable electrical contact with the critical nodes of the sample.

[0055] Step 3: Timing Calibration. Determine the timing relationship (synchronous, alternating, or partially overlapping) of the two laser beams according to experimental requirements. For precise synchronization, ensure both fiber optic links are of equal length. If a relative delay needs to be set, this can be achieved by replacing fiber optic patch cords with different lengths or adding delay fibers to the fiber optic links. Use the oscilloscope's trigger interface to verify whether the timing relationship of the two laser beams reaching the target point matches expectations.

[0056] Step 4: Synergistic Effect Test. Start the pulsed fiber laser output and acquire the electrical response waveform of the sample under test using an oscilloscope. According to the experimental plan, the following tests can be performed: 1. Single-path benchmark test: Turn on either the first or second optical path separately and record the device response under single-beam irradiation; 2. Dual-path synchronous test: Turn on both lasers simultaneously and record the device response under synchronous dual-beam irradiation; 3. Dual-path timing test: Set the relative delay between the two laser beams and record the device response under different timing conditions; 4. Angle-dependent test: Adjust the incident angle of the fiber probe and record the device response under different angle conditions. By comparing and analyzing the differences in device response under single-beam and dual-beam irradiation, the synergistic gain or suppression effect can be quantitatively evaluated.

[0057] Step 5: Data Processing and Analysis. Characteristic parameters such as peak current, integrated charge, rise time, and recovery time are extracted from the waveform data acquired by the oscilloscope. By comparing the changes in these characteristic parameters under different angles, power ratios, and timing conditions, a three-dimensional response surface of angle, power, and timing is constructed to reveal the changing patterns of the synergistic effect.

[0058] This embodiment, through the above design, achieves the opposite or opposite incident incidence of two pulsed laser beams at the same coordinate system and the same target point. The power of each beam is independently adjustable and calibrated online, and the optical path / timing can be calibrated. Relying on the calibrated micro-displacement and 360° angle adjustment of four universal probe clamps, continuous adjustable, readable, and lockable attitude and position control can be obtained without relying on electronically controlled motion. The structure of the double-sided probe stage and the hollow sample support stage enables front, back, and tilt illumination. Combined with oscilloscope trigger alignment and online reading of two energy channels, reproducible transient electrical response data can be obtained in the three-dimensional parameter space of angle-power-timing, which facilitates quantitative analysis such as synergistic gain / suppression, threshold change, and recovery dynamics.

[0059] To verify the effectiveness of the incident angle adjustment function of the system of the present invention, TCAD simulation verification was carried out in single-optical-path working mode. During the simulation, the laser pulse energy, pulse width, and irradiation position were kept constant, and only the laser incident angle θ was changed, which was set to 60°, 75°, 85°, 90°, 95°, 105°, and 120° respectively. Parameters such as peak current Imax, collected charge Qc, and response time window Δt in the transient response of the device were extracted.

[0060] From Table 1, Figure 5 and Figure 6 It can be seen that, under the condition that the laser pulse energy, pulse width and irradiation position remain unchanged, the transient response parameters of the device show a clear pattern as the incident angle changes.

[0061]

[0062] Table 1 Comparison of transient response parameters of the device at different incident angles

[0063] like Figure 5 As shown, as the laser incident angle gradually increases from 60° to 120°, the transient peak current Imax of the device generally shows an upward trend, increasing from 5.17 × 10⁻⁶. -4 A increased to 6.26 × 10 -4 A, an increase of approximately 21%. This indicates that under larger incident angles, the instantaneous carrier collection capability within the device's sensitive region is enhanced, leading to an increase in the peak transient current.

[0064] like Figure 6 As shown, the collected charge Qc remains relatively stable within the range of 60° to 90°, reaching a maximum value of approximately 0.092 pC near 90°. When the incident angle increases further, the collected charge decreases significantly, dropping to approximately 0.070 pC at 120°, a decrease of about 24%. This indicates that as the incident angle increases, the carrier collection efficiency gradually decreases, leading to a reduction in the total collected charge.

[0065] Furthermore, as can be seen from Table 1, the response time window Δt gradually decreased from 0.889 ns to 0.516 ns, indicating that the duration of the device's transient response was shortened under a larger incident angle.

[0066] The above results demonstrate that the laser incident angle is a crucial factor affecting the single-particle transient response of the device. By continuously adjusting the incident angle of the fiber optic probe, different characteristic parameters such as peak current, collected charge, and response duration can be obtained. This verifies that the dual-path multi-angle fiber optic probe pulsed laser irradiation simulation system proposed in this invention has the capability to conduct angle sensitivity studies and can provide technical support for the analysis of angle-power-time coupling effects.

[0067] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any changes made based on the design principles of the present invention, or any non-creative modifications made thereon, shall fall within the scope of protection of the present invention.

Claims

1. A dual-path, multi-angle fiber optic probe pulsed laser irradiation simulation system, characterized in that, include: A pulsed laser generating device, used to generate a pulsed laser beam with set parameters; An optical beam splitter is connected to the output end of the pulsed laser generating device and is used to split the pulsed laser beam into a first optical path and a second optical path. The beam splitting link components are respectively set on the first optical path and the second optical path, including a power adjustment unit for independently adjusting the laser power of each optical path and a power monitoring unit for real-time detection and calibration of the laser power of each optical path. The fiber optic probe assembly includes a first fiber optic probe connected to the end of a first optical path and a second fiber optic probe connected to the end of a second optical path; A sample carrier mechanism is used to place the sample of the semiconductor device under test. The sample carrier mechanism is provided with a hollow light-transmitting window to provide an incident channel for the fiber optic probe assembly. The probe adjustment mechanism is used to clamp and adjust the spatial position and angle of the first and second fiber optic probes, so that the two fiber optic probes are aligned with the same target point of the semiconductor device under test in a unified coordinate system and the incident angle and azimuth angle are continuously adjustable. An electrical detection device is used to collect the electrical response of a semiconductor device under test under laser irradiation, including an electrical probe electrically connected to the semiconductor device under test and a signal acquisition unit electrically connected to the electrical probe. The first and second fiber optic probes, through spatial positioning and timing coordination, form a dual-path multi-angle irradiation field in the working area of ​​the semiconductor device under test, which can be opposed or opposite in direction.

2. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to claim 1, characterized in that, The pulsed laser generating device includes a pulsed fiber laser and its driving control unit. The center wavelength range of the pulsed fiber laser covers the absorption band of semiconductor materials, the pulse width ranges from nanosecond to picosecond, the repetition frequency is adjustable, and the single pulse energy is controllable.

3. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to claim 1, characterized in that, The optical path beam splitting device includes an optical fiber isolator and an optical fiber splitter. The optical fiber isolator is connected to the output end of the pulsed laser generating device and is used to suppress backlight. The fiber optic splitter is connected to the output end of the fiber optic isolator and is used to split the pulsed laser beam into a first optical path and a second optical path according to a preset ratio.

4. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to claim 1, characterized in that, The power adjustment unit is a manually adjustable fiber optic attenuator with an adjustable attenuation range of at least 0dB to 30dB. The power monitoring unit includes a fiber optic sampling coupler and an energy meter. The main channel coupling ratio of the fiber optic sampling coupler is ≥99%, and the sampling channel coupling ratio is ≤1%. The energy meter is connected to the sampling channel and is used to read the sampling power of each optical path in real time and perform power calibration accordingly.

5. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to claim 1, characterized in that, The fiber optic link lengths of the first and second optical paths are equal or calibrated to achieve synchronous arrival of the two pulsed laser beams at the target point or a set relative delay.

6. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to claim 1, characterized in that, The numerical aperture range of the first and second fiber probes is 0.1 to 0.5, the core diameter range is from single-mode to multi-mode fiber specifications, and the working distance is adjustable to adapt to the irradiation requirements of sensitive areas of devices of different sizes.

7. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to claim 1, characterized in that, The signal acquisition unit is configured as an oscilloscope, which has a trigger interface connected to the trigger output of the pulsed laser generating device to establish a unified time reference and synchronously acquire the steady-state and transient electrical responses of the semiconductor device under test.

8. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to any one of claims 1 to 7, characterized in that, The probe adjustment mechanism includes a probe stage and a universal probe clamp. Multiple universal probe clamps are configured to hold a first fiber optic probe, a second fiber optic probe, and an electrical probe, respectively. Each universal probe clamp is equipped with three displacement adjustment knobs with scales corresponding to the X / Y / Z directions and one angle control knob with scales. Each knob has a locking structure to achieve repeated positioning.

9. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to claim 8, characterized in that, The probe station is configured as a double-sided probe station, on which an upper support plate and a lower support plate are arranged vertically. A notch is opened at the center of the upper and lower support plates to facilitate the coaxial arrangement of the sample support mechanism. The first optical fiber probe is placed on the upper support plate and the second optical fiber probe is placed on the lower support plate, so that the second optical fiber probe can approach or pass through the hollow light transmission window to achieve back or tilted incident under non-zero incident angle conditions.

10. The dual-optical-path multi-angle fiber optic probe pulsed laser irradiation simulation system according to claim 9, characterized in that, The sample carrying mechanism includes a sample stage for placing the semiconductor device sample under test and a manual XYZ displacement stage for supporting the sample stage. The manual XYZ displacement stage shares the same base and coordinate system with the probe adjustment mechanism.

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