A multi-wavelength laser simulation ionizing radiation effect test system

Abstract

The application discloses a kind of multi-wavelength laser simulation ionizing radiation effect test system based on straight line sliding platform quick conversion light path, and the system includes three parts of multi-wavelength pulsed laser light source, multi-channel attenuation system and measurement and control system.The application is matched by moving side-view optical path along the direction of straight line sliding platform to realize multi-wavelength laser and attenuation system, and the irradiation of pulsed laser to the device to be measured is realized by measurement and control system, and the instantaneous response electrical signal of the device to be measured and the image information of device irradiation area are collected and recorded, to simulate the ionizing radiation effect of radiation source such as gamma ray on semiconductor device.The system has the characteristics of quick conversion light path, safety, etc., and can effectively solve the problems of single laser wavelength, complex switching light path, etc., in traditional semiconductor device laser simulation system, and provides a technical approach for laser simulation system of ionizing irradiation effect of different bandgap semiconductor devices.

Description

Technical Field

[0001] This invention pertains to semiconductor device radiation effect technology, and specifically relates to a multi-wavelength laser simulation ionizing radiation effect test system. Background Technology

[0002] In recent years, with the rapid development of electronic technology, more and more semiconductor devices have been applied in important fields such as aerospace, nuclear technology, medicine, and military. These applications often involve various types of radiation, including gamma rays, X-rays, neutrons, and high-energy particles, which can generate ionizing radiation effects within semiconductor devices. This greatly increases the probability of electronic device failure and seriously affects the stability and lifespan of electronic devices.

[0003] To improve the radiation resistance of devices and electronic equipment, it is crucial to conduct simulated testing of devices under radiation environments. Laser simulation technology, with its advantages of safety, reliability, and good repeatability, is widely used in ionization effect simulation experiments. Different laser wavelengths produce different penetration depths and ionization ranges within materials, which are important factors affecting laser simulation. On the one hand, different laser wavelengths have different penetration depths in materials. To produce a near-uniform ionization effect in the active region of the device, the penetration depth must cover the thickness of the active region, which requires the wavelength to be as long as possible. On the other hand, the laser wavelength must satisfy the requirement that the photon energy is greater than the bandgap of the semiconductor material, but the higher the photon energy, the shorter the corresponding laser wavelength must be. Therefore, the selection of wavelength is often a compromise for devices with different structures and material systems. With the rapid development of semiconductor devices and the continuous expansion of material systems, the demand for laser simulation of narrow-bandgap semiconductor devices is gradually increasing. Single-wavelength lasers can no longer meet the testing needs of diverse material systems. Therefore, designing a multi-wavelength laser simulation ionization radiation effect test system has extremely important practical significance.

[0004] Currently, laser simulation ionizing radiation effect test systems often only have one or at most two working wavelengths. Even if other wavelengths of laser output can be achieved by replacing the frequency doubling module, the subsequent optical path adjustment process is extremely complex and cumbersome. Moreover, the laser output position is often different, causing the beam to deviate, which affects the accuracy and stability of the laser simulation system. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a laser simulation ionizing radiation effect test system that can realize rapid switching of optical paths by a linear slide, addressing the issue that the optical path adjustment process of the current multi-wavelength laser simulation ionizing radiation effect test equipment is complicated and easily leads to beam deviation when changing the frequency doubling module.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is a multi-wavelength laser simulation ionizing radiation effect test system, including a multi-wavelength pulsed laser source, a multi-channel attenuation system and a measurement and control system; the output end of the multi-wavelength pulsed laser source is connected to the input end of the multi-channel attenuation system through a cable, and the output end of the multi-channel attenuation system is connected to the measurement and control system through a cable.

[0007] The multi-wavelength pulsed laser source is a pulsed laser with several frequency doubling modules. Different frequency doubling modules are used to generate lasers of different wavelengths, and different wavelengths of lasers have different emission positions. Multi-wavelength lasers can be generated by changing different frequency doubling modules in the pulsed laser.

[0008] The multi-path attenuation system includes two linear slides and multiple attenuation paths. It is used to input the received multi-wavelength pulsed laser into the attenuation optical path corresponding to the current received wavelength for attenuation processing and then output it to the measurement and control system.

[0009] The linear slide is a linear slide with built-in double reflectors. Multiple attenuation paths are connected in parallel between the two linear slides. Each attenuation path corresponds to a different wavelength of laser. The laser can be transmitted in different attenuation optical paths by adjusting the position of the reflectors in the linear slide. In the linear slide connected to the multi-wavelength pulsed laser source, one reflector is used to receive the laser from the multi-wavelength pulsed laser source into the optical transmission channel of the linear slide, and the other reflector is used to reflect the laser from the optical transmission channel into the attenuation optical path corresponding to the received laser. In the linear slide connected to the measurement and control system, one reflector is used to receive the laser from the attenuation optical path into the optical transmission channel of the linear slide, and the other reflector is used to reflect the laser from the optical transmission channel into the cable connected to the measurement and control system.

[0010] The measurement and control system is used to irradiate the device under test with laser light from a multi-channel attenuation system, acquire and record the transient response electrical signals of the device under test, and image the irradiated area of ​​the device.

[0011] Specifically, in each attenuation path, a half-wave plate, a neutral filter wheel, a combined attenuator, and a beam splitter are cascaded in sequence. The input end of the half-wave plate serves as the input end of the attenuation path, one output end of the beam splitter serves as the output end of the attenuation path, and the other output end of the beam splitter is connected to the energy meter probe.

[0012] Furthermore, the measurement and control system is also used to adjust the parameters of the pulsed laser in the multi-wavelength pulsed laser source, the placement position of the device under test in the measurement and control system, and the setting of the attenuation path in the multi-path attenuation system. Specifically, adjusting the attenuation path settings in the measurement and control system involves adjusting the combined attenuator within the attenuation path.

[0013] Specifically, the multi-wavelength pulsed laser source is a solid-state laser capable of generating wavelengths of 1064nm, 532nm, and 355nm.

[0014] Furthermore, the measurement and control system includes a custom-designed lens barrel for receiving the attenuated beam, a converter disposed below the custom-designed lens barrel, a three-dimensional displacement stage for placing the device under test (DUT), a probe disposed on the side of the three-dimensional displacement stage, and a CCD imaging device with built-in LED illumination disposed above the displacement stage. The measurement and control system also includes a computer, a DC regulated power supply, and an oscilloscope. The computer is connected to the CCD imaging device via cables, and the DC regulated power supply and oscilloscope are connected to the DUT and the three-dimensional displacement stage via cables.

[0015] Optionally, the converter is a converter equipped with a focusing objective and a beam expander.

[0016] Specifically, the reflector is a dielectric film laser reflector.

[0017] The beneficial effects of this invention are: it features rapid matching of multi-wavelength lasers with corresponding attenuation optical paths, allowing for quick switching to different wavelengths and corresponding attenuation optical paths by adjusting the linear slide of the built-in reflector according to experimental needs. This covers the laser simulation requirements of narrow-gap to wide-gap semiconductor devices. The spot size and repetition rate are adjustable, enabling focused positioning of sensitive units and layers within the device, as well as beam expansion to study the global radiation response of the entire chip and even the device. This solves the problems of single wavelength, complex optical path conversion, and difficulty in multi-wavelength switching in current laser simulation systems, improving the accuracy and stability of laser simulation systems and providing a more comprehensive testing environment for the study of radiation effects in semiconductor devices. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of one embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the linear slide structure containing two reflectors according to the present invention.

[0020] The names corresponding to the reference numerals in the attached figures are as follows:

[0021] 1 - Pulsed laser, 2 - Frequency doubling module (2ω), 3 - Dichroic mirror group (2ω), 4 - Frequency doubling module (3ω),

[0022] 5-Dichroic mirror group (3ω), 6-Linear slide, 7-Reflector, 8-Half-wave plate, 9-Neutral filter wheel, 10-Combined attenuator, 11-Energy meter probe, 12-Beam splitter prism, 13-Customized lens tube, 14-Transformer, 15-Focusing objective lens, 16-Beam expander, 17-Probe, 18-Device under test, 19-3D moving stage, 20-CCD

[0023] Camera, 21-LED light source, 22-Cable, 23-Computer, 24-Oscilloscope, 25-Regulated DC power supply. Detailed Implementation

[0024] The present invention will now be described in detail with reference to the accompanying drawings.

[0025] like Figure 1 As shown, the multi-wavelength laser simulation ionizing radiation effect test system consists of three parts: a multi-wavelength pulsed laser source, a multi-path attenuation system, and a measurement and control system.

[0026] The multi-wavelength pulsed laser source can generate three wavelengths (1064 / 532 / 355nm) of pulsed laser by changing different frequency doubling modules, and the emission position of different wavelengths is different;

[0027] The multi-path attenuation system receives multi-wavelength pulsed lasers through a linear slide containing dual mirrors, and selects a corresponding attenuation optical path for a certain wavelength according to requirements. After attenuation, the optical path is connected to the measurement and control system.

[0028] The measurement and control system is connected to the multi-wavelength pulsed laser source and the multi-channel attenuation system via cables. It is used to adjust the pulsed laser parameters and the corresponding precise attenuation of the laser, collect and record the transient response electrical signals of the device under test, and image the irradiated area of ​​the device.

[0029] The laser that generates pulsed laser sources with wavelengths of 1064 / 532 / 355nm is an Nd:YAG solid-state laser. The laser pulse width is 5-6ns, and the highest single-pulse energy can reach 400mJ. It can be used for laser simulation irradiation experiments on semiconductor devices made of materials such as Si, GaN, Ga2O3, and SiC. The multi-wavelength pulsed laser source includes a pulsed laser 1, a 2ω (ω refers to the doubling frequency) frequency doubling module 2, a 2ω dichroic mirror group 3, a 3ω frequency doubling module 4, and a 3ω dichroic mirror group 5. Pulsed laser 1 can generate a laser with a wavelength of 1064nm; adding a 2ω frequency doubling module 2 and a 2ω dichroic mirror group 3 to pulsed laser 1 generates a laser with a wavelength of 532nm; further adding a 3ω frequency doubling module 4 and a 3ω dichroic mirror group 5 after the 2ω frequency doubling module 2 generates a laser with a wavelength of 355nm.

[0030] Due to the inherent design limitations of solid-state lasers, the output position shifts slightly after each replacement of the frequency doubling module and dichroic mirror group. To accommodate this shift, a multi-path attenuation system is implemented, comprising a linear slide 6, a reflector 7, a half-wave plate 8, a neutral density filter wheel 9, a combined attenuator 10, an energy meter probe 11, and a beam splitter prism 12.

[0031] like Figure 2As shown, in the light propagation path, the multi-wavelength pulsed laser source outputs laser light to the multi-path attenuation system. First, it passes through the front linear slide 6 containing two sliding mirrors 7 and is output to one attenuation path through double reflection. On the attenuation path, it first passes through a half-wave plate 8 for polarization direction selection. Then, the neutral density filter wheel 9 is used to achieve the first stage of attenuation and complete the coarse adjustment. Then, the combined attenuator 10 composed of two half-wave plates is used to achieve the second stage of attenuation and complete the fine adjustment. Subsequently, the beam is split into beams of equal energy by a beam splitter prism 12. One beam is transmitted to the energy meter probe 11 for real-time monitoring of the laser energy, and the other beam passes through the rear linear slide 6 containing two mirrors 7 and is output to the measurement and control system through double reflection.

[0032] The measurement and control system includes a custom-designed lens tube 13, a converter 14, a focusing objective lens 15, a beam expander 16, a probe 17, a device under test 18, a three-dimensional moving stage 19, a CCD camera 20, an LED light source 21, cables 22, a computer 23, an oscilloscope 24, and a regulated DC power supply 25.

[0033] The laser output from the multi-path attenuation system reaches the measurement and control system. It first enters the customized lens tube 13 and then enters the converter 14 for focusing or beam expansion. If focusing is required, the beam output from the converter 14 is input to the focusing objective lens 15; if beam expansion is required, the beam output from the converter 14 is input to the beam expander lens 16. The converter 14 allows manual selection of whether to output the beam to the focusing objective lens 15 or the beam expander lens 16. After focusing or expansion, the beam ultimately radiates a spot onto the device under test 18, achieving uniform or area coverage of the sensitive area of ​​the test sample. If a frequency doubling module is added to double the wavelength to obtain 532nm or 355nm, then simply replace the reflector with one suitable for the 532nm or 355nm band, rotate the converter 14 to switch to the corresponding beam expander or focusing objective, and then move the reflector 7 along the linear slide 6 to the 532nm or 355nm attenuation path to achieve rapid switching of the laser wavelength and attenuation path.

[0034] Since the output position of the pulsed laser is slightly different after the frequency doubling module is replaced, the two dielectric film laser reflectors 7 can be moved along the linear slide 6 and adjusted to the appropriate position. That is, the first reflector is used to access the laser source and reflect the light to the second reflector. Then, the second reflector is adjusted to reflect the light again. The corresponding attenuation optical paths with wavelengths of 1064nm, 532nm and 355nm can be accessed as needed, and finally reach the measurement and control system. This not only solves the problem of different output positions of the three wavelengths of solid-state laser, but also has the ability to quickly switch the corresponding wavelength attenuation optical path.

[0035] The custom-designed lens barrel 13 and converter 14 of the measurement and control system irradiate the device under test 18 (DUT 18), which is placed on the three-dimensional displacement stage 19, with laser output from the attenuated optical path, to simulate the ionizing radiation effect. Since the laser can damage the CCD camera 20, the custom-designed lens barrel is not coaxial with the CCD camera. After the LED light source 21 illuminates the DUT 18, it is imaged by the CCD camera 20, facilitating probe insertion by the probe station 17. The oscilloscope 24 receives the electrical signal from the probe 17 and displays the waveform, recording and analyzing the electrical performance response of the DUT. The computer 23 receives the imaging data from the CCD camera 20 and positions the laser spot, facilitating precise spot location and accurate evaluation of spot size. It can also control laser parameters, the three-dimensional displacement stage, and the combined attenuator. The DUT 18 and the three-dimensional displacement stage 19 are transmitted to the computer 23 via cable 22. The DC regulated power supply 25 biases the DUT 18 and powers the three-dimensional displacement stage 19.

[0036] Through the above design, the embodiment features rapid adjustment of the corresponding attenuation optical path for multiple wavelengths. It can switch to the corresponding attenuation optical path with wavelengths of 1064nm, 532nm and 355nm in a short time according to the experimental requirements by adjusting the linear slide of the built-in reflector. It can cover the laser simulation requirements of narrow bandgap semiconductor devices and wide bandgap semiconductor devices. The spot size and repetition rate are adjustable. It can focus and locate the sensitive unit and sensitive layer in the device, or expand the beam to study the global radiation response of the entire device or even the chip.

[0037] The above embodiments are merely one implementation method of the present invention. The wavelengths used include, but are not limited to, 1064nm, 532nm and 355nm. Any modifications made to the main design of the present invention that are not of substantial significance but still solve the same technical problem as the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-wavelength laser simulation system for ionizing radiation effects, characterized in that, It includes a multi-wavelength pulsed laser source, a multi-channel attenuation system, and a measurement and control system; the output of the multi-wavelength pulsed laser source is connected to the input of the multi-channel attenuation system via a cable, and the output of the multi-channel attenuation system is connected to the measurement and control system via a cable. The multi-wavelength pulsed laser source is a pulsed laser with frequency doubling modules configured with different frequencies. The frequency doubling modules with different frequencies are used to generate lasers of different wavelengths, and the lasers of different wavelengths have different output positions. Multi-wavelength lasers can be generated by replacing different frequency doubling modules in a pulsed laser. The multi-path attenuation system includes two linear slides and multiple attenuation paths, which are used to input the received multi-wavelength pulsed laser into the attenuation path corresponding to the current received wavelength for attenuation processing and then output to the measurement and control system. The linear slide is a linear slide with a built-in reflector. Multiple attenuation paths are connected in parallel between two linear slides. Each attenuation path corresponds to a different wavelength of laser. The laser is transmitted in different attenuation paths by adjusting the position of the reflector in the linear slide. In the linear slide connected to the multi-wavelength pulsed laser source, one reflector is used to receive the laser from the multi-wavelength pulsed laser source into the optical transmission channel of the linear slide, and the other reflector is used to reflect the laser from the optical transmission channel into the attenuation path corresponding to the received laser. In the linear slide connected to the measurement and control system, one reflector is used to receive the laser from the attenuation path into the optical transmission channel of the linear slide, and the other reflector is used to reflect the laser from the optical transmission channel into the cable connected to the measurement and control system. The measurement and control system is used to irradiate the device under test with laser from the multi-channel attenuation system, acquire and record the transient response electrical signals of the device under test, and image the irradiated area of ​​the device. The measurement and control system includes a custom-designed telescope tube, converter, focusing objective lens, beam expander, probe, device under test, 3D moving stage, CCD camera, LED light source, computer, oscilloscope, and regulated DC power supply. The laser beam from the attenuation path first passes through a custom-designed lens barrel, then is focused by a focusing objective or expanded by a beam expander via a converter. The focused or expanded laser beam then irradiates the device under test (DUT) placed on a three-dimensional moving stage, simulating the ionizing radiation effect. After the LED light source illuminates the DUT, a CCD camera images the image, facilitating probe insertion. An oscilloscope receives the electrical signal from the probe and displays the waveform, recording and analyzing the electrical performance response of the DUT. A computer receives the imaging data from the CCD camera and positions the laser beam. A DC regulated power supply is used to bias the DUT and power the three-dimensional movement.

2. The multi-wavelength laser simulation ionizing radiation effect test system as described in claim 1, characterized in that, In each attenuation path, a half-wave plate, a neutral filter wheel, a combined attenuator, and a beam splitter are cascaded in sequence. The input end of the half-wave plate serves as the input end of the attenuation path, one output end of the beam splitter serves as the output end of the attenuation path, and the other output end of the beam splitter is connected to the energy meter probe.

3. The multi-wavelength laser simulation ionizing radiation effect test system as described in claim 2, characterized in that, The measurement and control system is also used to adjust the parameters of the pulsed laser in the multi-wavelength pulsed laser source, the placement position of the device under test in the measurement and control system, and the setting of the attenuation path in the multi-channel attenuation system.

4. The multi-wavelength laser simulation ionizing radiation effect test system as described in claim 3, characterized in that, The setting of the attenuation path adjustment in the measurement and control system specifically involves adjusting the combined attenuator in the attenuation path.

5. The multi-wavelength laser simulation ionizing radiation effect test system as described in claim 4, characterized in that, The reflector is a dielectric film laser reflector.

6. The multi-wavelength laser simulation ionizing radiation effect test system as described in claim 1, characterized in that, The multi-wavelength pulsed laser source generates three types of pulsed lasers with wavelengths of 1064 nm, 532 nm, and 355 nm.

7. The multi-wavelength laser simulation ionizing radiation effect test system as described in claim 6, characterized in that, The multi-wavelength pulsed laser source includes a pulsed laser, a 2ω frequency doubling module, a 2ω dichroic mirror group, a 3ω frequency doubling module, and a 3ω dichroic mirror group. The pulsed laser directly outputs a laser with a wavelength of 1064 nm. After cascading a 2ω frequency doubling module and a 2ω dichroic mirror group at the output of the pulsed laser, a laser with a wavelength of 532 nm is output. After cascading a 2ω frequency doubling module, a 3ω frequency doubling module, and a 3ω dichroic mirror group sequentially at the output of the pulsed laser, a laser with a wavelength of 355 nm is output, where ω is the doubling frequency.

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