A system and method for testing drift characteristics of semiconductor drift chamber detector

Abstract

The present invention relates to the field of semiconductor drift chamber detector measurement, and specifically to a test system and method for the drift characteristics of a semiconductor drift chamber detector. The test system includes a double-sided probe station, a semiconductor drift chamber detector, a first dual-channel digital multimeter, a second dual-channel digital multimeter, a laser and an optical fiber clamp. The double-sided probe station is used to fix and connect the detector, the digital multimeter applies bias and collects data respectively, and the laser illuminates the back of the detector through an optical fiber. During the test, the laser wavelength is first selected and the light power is adjusted, the detector is placed in a double-sided probe station in a dark room and connected to the equipment, the voltage is set and the current is monitored after illumination, the illumination position is adjusted, and the lateral drift characteristics are judged based on the current difference at different illumination positions. Whether it is qualified. Compared with traditional integrated testing, this test system and method effectively reduces the test time, improves the device iteration speed, and can conveniently characterize the lateral drift characteristics of electrons in semiconductor drift chamber detectors.

Description

Technical Field

[0001] The invention relates to the field of semiconductor drift chamber detector measurement, and in particular to a system and method for testing drift characteristics of a semiconductor drift chamber detector. Background Art

[0002] The semiconductor drift chamber detector is a high-performance semiconductor detector with many advantages, such as high sensitivity, high energy resolution, high position resolution, fast electronic signal readout speed, high operating temperature, low noise, small size, light weight and low energy consumption. These characteristics make it the best choice for detecting X-rays.

[0003] The lateral drift characteristic of the semiconductor drift chamber detector is one of its basic and important performances. When the detector is working, a reverse voltage is applied to the pn junctions on both sides of the device, thereby generating a potential well (for electrons) in the device body. At this time, if a potential difference is applied to the drift electrode, a transverse electric field will be generated in the device. This transverse electric field will bend the potential well, thereby forcing the signal electrons generated by the incident radiation to drift toward the anode electrode under the action of the electric field. On the one hand, this lateral drift characteristic enables the semiconductor drift chamber detector to accurately measure the position of the incident particle (the signal electrons will drift to the anode electrode along a specific path under the guidance of the transverse electric field. By measuring the time or position of the electrons arriving at the anode electrode, the original position of the incident particle can be inferred). On the other hand, the lateral drift characteristic of the semiconductor drift chamber detector is also closely related to the uniformity of its internal electric field distribution (a uniform electric field can ensure that the signal electrons are subjected to a constant force during the drift process, thereby maintaining a stable drift velocity), which helps to improve the position resolution and energy resolution of the detector.

[0004] At present, conventional testing usually requires the integration of multiple devices, such as a stable and known energy radiation source (X-ray source or particle beam), double-sided device packaging, back-end electronic matching circuits, and precise measurement equipment (energy spectrum analyzer, counter, preamplifier, etc.). Complex test equipment and matching circuits greatly reduce the feedback efficiency of the success or failure of the device, occupy a long test time, and are not conducive to the rapid iteration of products. Therefore, in order to improve the success feedback rate of the device, it is a technical problem that technicians in this field need to solve urgently to provide a simple test system and method for the drift characteristics of semiconductor drift chamber detectors. Summary of the invention

[0005] In order to solve the defects existing in the above-mentioned prior art, the present invention provides a testing system and method for the drift characteristics of a semiconductor drift chamber detector, so as to conveniently characterize the drift characteristics of electrons in a semiconductor drift chamber detector in a transverse electric field, improve the device performance feedback efficiency, and accelerate product iteration.

[0006] In order to solve the above technical problems, the present invention is implemented by the following technical solutions:

[0007] In a first aspect, the present invention provides a test system for drift characteristics of a semiconductor drift chamber detector, the test system comprising:

[0008] A double-sided probe station, wherein a plurality of probes are arranged on the double-sided probe station;

[0009] A semiconductor drift chamber detector, the semiconductor drift chamber detector is placed on the double-sided probe station and connected to the probe, and the back of the semiconductor drift chamber detector is arranged upward; the front of the semiconductor drift chamber detector includes an anode electrode, an innermost drift ring electrode and an outermost drift ring electrode; the back of the semiconductor drift chamber detector includes a back electrode;

[0010] A first dual-channel digital multimeter, wherein two channels of the first dual-channel digital multimeter are respectively connected to the innermost drift ring electrode and the back electrode through the probe;

[0011] A second dual-channel digital multimeter, wherein two channels of the second dual-channel digital multimeter are respectively connected to the anode electrode and the outermost drift ring electrode through the probe; the second dual-channel digital multimeter is connected to a computer terminal;

[0012] A laser is connected to an optical fiber, and an output end of the optical fiber is used to irradiate the back side of the semiconductor drift chamber detector.

[0013] As a further optimization scheme of the present invention, the test system also includes a fiber optic clamp, which is used to clamp the optical fiber and drive the optical fiber to move in different directions to adjust the irradiation position of the optical fiber on the back side of the semiconductor drift chamber detector.

[0014] As a further optimization solution of the present invention, the laser includes a laser controller and a laser light source, and the laser light source includes a light source in the ultraviolet light, visible light and near-infrared bands.

[0015] As a further optimization solution of the present invention, the incident path of the optical fiber is perpendicular to the plane of the double-sided probe station.

[0016] As a further optimization solution of the present invention, the first dual-channel digital multimeter and the second dual-channel digital multimeter are connected to a common ground.

[0017] In a second aspect, the present invention provides a method for testing drift characteristics of a semiconductor drift chamber detector, using the semiconductor drift chamber detector drift characteristics testing system in the above scheme, the testing method comprising:

[0018] S1, select the laser wavelength to be measured and adjust the laser output light power;

[0019] S2, placing the semiconductor drift chamber detector to be tested on a double-sided probe table in a closed darkroom, and connecting a first dual-channel digital multimeter and a second dual-channel digital multimeter to the innermost drift ring electrode, the back electrode, the anode electrode and the outermost drift ring electrode respectively through a plurality of probes;

[0020] S3, irradiating the optical signal obtained in step S1 to the micro-region on the back side of the semiconductor drift chamber detector via an optical fiber;

[0021] S4, through the control of the first dual-channel digital multimeter, the first bias voltage and the second bias voltage are fixedly output on the innermost drift ring electrode and the back electrode respectively; through the control of the second dual-channel digital multimeter, the anode electrode is fixed at 0V, and the Sweep voltage is scanned on the outermost drift ring electrode, and the anode electrode current signal is monitored by the computer terminal;

[0022] S5, by gradually adjusting the different illumination positions of the optical fiber, current signals at multiple different illumination positions are obtained; if the current difference at different illumination positions is less than the preset value, the lateral drift characteristic of the semiconductor drift chamber detector is judged to be qualified, and other performance test links are entered; if the current difference at different illumination positions is greater than the preset value, the lateral drift characteristic of the semiconductor drift chamber detector is judged to be unqualified.

[0023] As a further optimization scheme of the present invention, the absolute value of the bias voltage of the back electrode is greater than the absolute value of the longitudinal depletion voltage of the semiconductor drift chamber detector, and the bias voltage of the outermost drift ring electrode does not exceed twice the longitudinal depletion voltage of the semiconductor drift chamber detector.

[0024] As a further optimization solution of the present invention, the illumination position of the optical fiber is adjusted in a manner of gradually moving radially from the center to the edge of the semiconductor drift chamber detector.

[0025] As a further optimization scheme of the present invention, the first bias voltage and the second bias voltage are both negative voltages, the absolute value of the first bias voltage is smaller than the absolute value of the second bias voltage, and the preset value is 0.1uA; the preset current value on the innermost drift ring electrode and the outermost drift ring electrode is 10-50 uA.

[0026] As a further optimization scheme of the present invention, in step S4, the voltages of the innermost drift ring electrode and the outermost drift ring electrode are adjusted according to the current signal data collected during the test process, so that a linear drift track can be formed inside the semiconductor drift chamber detector.

[0027] Compared with the prior art, the semiconductor drift chamber detector drift characteristic testing system and method provided by the present invention, through a specific system configuration and testing process, show significant technical effects in improving test efficiency, reducing costs, and accurately judging device performance, as follows:

[0028] 1. Greatly improved test efficiency: Traditional testing requires the integration of multiple devices, such as stable radiation sources, double-sided packaging devices, back-end electronic matching circuits and precise measurement equipment, etc. The operation is cumbersome and the test time is lengthy. The present invention only requires simple equipment such as lasers, double-sided probe stations, 4 probes, 2 digital multimeters, etc. Through a unique test process, such as adjusting the laser, setting voltage scanning, monitoring current signals, etc., the drift characteristics of the semiconductor drift chamber detector can be quickly tested, effectively reducing the test time and accelerating the product iteration speed.

[0029] 2. Significantly reduced testing costs: The complex and expensive equipment used in traditional testing, such as radiation sources such as X-ray sources or particle beams, precise measurement equipment such as energy spectrum analyzers, and back-end electronic matching circuits, has been abandoned, thus avoiding high equipment purchase and maintenance costs. At the same time, the simplified testing process reduces the consumption of manpower and material resources during the testing process, reducing the overall testing cost.

[0030] 3. Accurately judge the performance of the device: Use a laser to illuminate the back of the semiconductor drift chamber detector to generate a light response, use a digital multimeter to set appropriate bias and voltage scans on different electrodes, and monitor the anode electrode current signal through the computer. In addition, by gradually adjusting the optical fiber illumination position, the current difference at different illumination positions is used to determine whether the lateral drift characteristics are qualified. This test method can accurately reflect the drift characteristics of electrons in the lateral electric field in the semiconductor drift chamber detector, and provide an accurate basis for whether to conduct other performance tests in the future. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of a test system for drift characteristics of a semiconductor drift chamber detector according to the present invention.

[0032] Figure 2 for Figure 1 Schematic diagram of the connection structure of the three wires at A on the front side of the semiconductor drift chamber detector.

[0033] Figure 3 The present invention is a flow chart of a method for testing drift characteristics of a semiconductor drift chamber detector.

[0034] Figure 4 Schematic diagram of the structure of the front and back sides of an exemplary device of the present invention; wherein a is the front side of the device, and b is the back side of the device.

[0035] Figure 5Schematic diagram of electrode wiring of an exemplary device of the present invention.

[0036] Figure 6 This is a data graph verifying the drift characteristics of an exemplary device of the present invention.

[0037] In the figure: 1-laser; 2-optical fiber; 3-semiconductor drift chamber detector; 4-double-sided probe station; 5-first dual-channel digital multimeter; 6-second dual-channel digital multimeter; 7-computer terminal; 8-darkroom; 301-anode electrode; 302-innermost drift ring electrode; 303-outermost drift ring electrode; 304-guard ring; 305-back electrode. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the technical solution of the present invention, the preferred implementation scheme of the present invention is described below in conjunction with specific embodiments. However, it should be understood that the drawings are only used for exemplary description and cannot be understood as a limitation on this patent. In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. The positional relationship described in the drawings is only for exemplary description and cannot be understood as a limitation on this patent.

[0039] Semiconductor drift chamber detectors, such as the representative nuclear radiation detector - silicon drift chamber detector (SDD), have significant advantages in energy resolution and count rate compared with other types of detectors (such as Si (Li), high purity germanium and PIN detectors). However, in conventional testing, multiple conditions usually need to be met, such as a radiation source (X-ray source or particle beam) that can generate stable and known energy, double-sided packaging of the device, back-end electronic matching circuits, and precise measurement equipment (energy spectrum analyzer, counter, preamplifier, etc.). In contrast, the evaluation method provided by the present invention can easily and effectively determine in advance whether the device has a lateral drift characteristic, so as to choose whether it is necessary to perform other performance verifications, such as energy resolution testing. This method has a wide range of applications, greatly saves equipment costs and testing time, and can also accurately reflect the collection efficiency of the device.

[0040] like Figure 1 and Figure 2 As shown, the present invention provides a test system for drift characteristics of a semiconductor drift chamber detector, the test system comprising a double-sided probe station 4, a semiconductor drift chamber detector 3, a first dual-channel digital multimeter 5, a second dual-channel digital multimeter 6, a laser 1 and an optical fiber clamp.

[0041] In some examples, the double-sided probe station 4 uses a double-sided probe station 4 with high-precision displacement control. Four probes are fixed on the double-sided probe station 4, which are used to connect the four electrodes of the semiconductor drift chamber detector 3 (anode electrode 301, innermost drift ring electrode 302, outermost drift ring electrode 303, back electrode 305), and a microscope and a precision displacement stage are integrated. The microscope is convenient for observing the connection between the probe and the detector electrode. The precision of the precision displacement stage can reach 1μm, and the position of the detector can be accurately controlled in the X and Y directions to ensure the accurate connection between the probe and the detector electrode. The position can be flexibly adjusted before the probe contacts the electrode, and the detector can be stably fixed after contact. Before the probe is inserted into the device electrode, it can be freely moved through the precision displacement stage, and then the relevant knob of the probe is fine-tuned to insert the needle into the device electrode. At this time, the device is fixed and cannot be moved on the probe station, and then the position of the light source is moved by adjusting the optical fiber clamp.

[0042] like Figure 4 As shown, in some examples, the semiconductor drift chamber detector 3 is placed on a double-sided probe station 4 and connected to a probe, the front side of the semiconductor drift chamber detector 3 includes an anode electrode 301, an innermost drift ring electrode 302, an outermost drift ring electrode 303 and a guard ring 304, and the back side of the semiconductor drift chamber detector 3 is an incident side, including a back electrode 305.

[0043] like Figure 5 As shown, in some examples, the dual-channel digital multimeter is a multi-purpose electronic measuring instrument, which is mainly used to measure voltage, current and resistance, and is mainly used for current-voltage testing here. Among them, the A channel of the first dual-channel digital multimeter 5 is connected to the innermost drift ring electrode 302 through a probe, and the B channel is connected to the back electrode 305 through a probe; the first dual-channel digital multimeter 5 can use a dual-channel digital multimeter 2636b, which is used to provide a fixed voltage, and the bias output accuracy can reach 0.01V to ensure the stable establishment of the electric field inside the detector. The A channel of the second dual-channel digital multimeter 6 is connected to the anode electrode 301 through a probe, and the B channel is connected to the outermost drift ring electrode 303 through a probe; the second dual-channel digital multimeter 6 is also connected to the computer terminal 7. The second dual-channel digital multimeter 6 can use a dual-channel digital multimeter 2636a, which is used for current-voltage function relationship data acquisition, and the collected current-voltage function relationship data is transmitted to the computer terminal 7 in real time for subsequent analysis and processing.

[0044] In some examples, laser 1 includes a laser controller and a laser light source. The laser light source includes a light source in the ultraviolet, visible and near-infrared bands. Light of different wavelengths can be selected according to test requirements. An optical fiber 2 is connected to the laser 1, and the output end of the optical fiber 2 is used to irradiate the back of the semiconductor drift chamber detector 3. It is mainly used to irradiate semiconductor drift chamber devices to generate light response. A modulation module is integrated inside the laser controller, which can be used to modulate the frequency of the light source signal within a certain range.

[0045] In some examples, a fiber clamp is used to clamp the optical fiber 2, which can drive the optical fiber 2 to move precisely in three-dimensional space with a movement accuracy of up to 1 μm, and can ensure that the incident path of the optical fiber 2 is perpendicular to the plane of the double-sided probe station 4, thereby accurately adjusting the irradiation position of the optical fiber 2 on the back of the detector.

[0046] In addition, to ensure the accuracy of the test, the entire test system should be placed in a closed darkroom 8 to avoid external light interference. The first dual-channel digital multimeter 5 and the second dual-channel digital multimeter 6 need to be connected to a common ground to reduce the impact of electrical interference on the test results.

[0047] Based on the above test system, Figure 3 As shown, this embodiment provides a method for testing drift characteristics of a semiconductor drift chamber detector, and the testing method includes:

[0048] S1, select a laser 1 of a suitable wavelength according to the test requirements, and accurately adjust the output optical power of the laser 1 through the laser controller to ensure that the optical power is stable and meets the test requirements. For example, in this embodiment, the optical power is adjusted to a specific value so that the detector can produce an obvious optical response while avoiding damage to the detector caused by excessive optical power.

[0049] S2, carefully place the semiconductor drift chamber detector 3 to be tested on the double-sided probe station 4 in the closed darkroom 8, and connect the first dual-channel digital multimeter 5 and the second dual-channel digital multimeter 6 to the innermost drift ring electrode 302, the back electrode 305, the anode electrode 301 and the outermost drift ring electrode 303 of the detector respectively through the probe. During the connection process, with the help of the microscope and precision translation stage of the double-sided probe station 4, ensure that the probe is tightly and accurately connected to the electrode to avoid virtual connection or poor contact affecting the test results. One end of the four probes is connected to the innermost drift ring electrode 302, the back electrode 305, the anode electrode 301 and the outermost drift ring electrode 303 of the device, and the other end is connected to the dual-channel digital multimeter through the BNC three-coaxial test line.

[0050] S3, irradiate the optical signal obtained in step S1 to the micro-area on the back side of the semiconductor drift chamber detector 3 via the optical fiber 2. During the irradiation process, the position of the optical fiber 2 must be kept stable to avoid shaking that may cause inaccurate irradiation position.

[0051] S4, controlled by the first dual-channel digital multimeter 5, the first bias and the second bias are fixedly output on the innermost drift ring electrode 302 and the back electrode 305 respectively; the absolute value of the bias of the back electrode 305 needs to be greater than the absolute value of the longitudinal depletion voltage of the semiconductor drift chamber detector 3, so as to ensure that the detector is in a suitable working state. If the back electrode bias does not reach the longitudinal depletion voltage, an effective depletion layer may not be formed inside the detector, causing the drift of the signal electrons to be disturbed, thereby affecting the accuracy of the test results. At the same time, the bias of the outermost drift ring electrode 303 does not exceed twice the longitudinal depletion voltage, otherwise it may cause the front and back sides of the device to be connected, generating a large leakage current, which will also interfere with the normal test process and the evaluation of the detector performance. Controlled by the second dual-channel digital multimeter, the anode electrode 301 is fixed to 0V, and the Sweep voltage scan is performed on the outermost drift ring electrode 303, and the changes in the current signal of the anode electrode 301 are monitored through the ACS Basic program of the computer terminal 7. Among them, the preset current value on the innermost drift ring electrode and the outermost drift ring electrode is 10-50 uA. If the current is too large, the device will heat up seriously, affecting the measurement accuracy.

[0052] S5, according to the current signal data collected during the test, the voltage of the innermost and outermost drift ring electrodes is adjusted to form a linear drift track inside the semiconductor drift chamber detector 3. By fine-tuning the voltage value multiple times and observing the change of the current signal, the optimal voltage setting is found to improve the electron collection efficiency of the anode electrode 301 and ensure the accuracy of the test results.

[0053] S6, gradually adjust the illumination position of the optical fiber 2 on the back of the detector by using the optical fiber clamp, gradually move radially from the center of the detector to the edge, and record the current signal of the anode electrode 301 once every certain distance (such as 100μm). If the current difference between different illumination positions is less than the preset value (the preset value is 0.1μA in this embodiment), it is determined that the lateral drift characteristic of the semiconductor drift chamber detector 3 is qualified, and other performance test links can be entered; if the current difference is greater than the preset value, it is determined that the lateral drift characteristic is unqualified.

[0054] Example 1

[0055] In this embodiment, a silicon drift chamber detector made by this laboratory was selected as the device for testing in a darkroom 8. The device size is 1.5×1.5 mm, the diameter of the circular anode electrode 301 is 120 μm, the innermost drift ring electrode 302 has a ring width of 10 μm, and the widths of the other drift ring electrodes are increased by 5 μm in sequence. The outermost drift ring electrode 303 has a ring width of 45 μm, and the drift ring spacing is 10 μm. The guard ring 304 has a ring width of 10 μm, and the ring spacing is 15 μm. The back electrode 305 has a ring width of 20 μm. A 366 nm laser 1 is selected and the optical fiber 2 is adjusted to 0.5 cm above the photosensitive micro-region of the device. The innermost drift ring electrode 302 and the back electrode 305 are biased with -10 V and -100 V (longitudinal depletion) respectively through a dual-channel digital multimeter 2636b, and the anode electrode 301 and the outermost drift ring electrode 303 are controlled by another dual-channel digital multimeter 2636a. The voltage of the anode electrode 301 of channel A is fixed at 0 V, and the outermost drift ring electrode 303 of channel B is scanned in the bias range of -100~-180 V.

[0056] See the actual effect diagram for details. Figure 1-Figure 6 . Figure 1 This is a structural schematic diagram of a semiconductor drift chamber detector testing system based on an optical fiber adjustable probe station of the present invention, which clearly shows the design concept and various system modules of the present invention. Figure 2 This is a schematic diagram of the connection structure of the three wires at point A in Figure 1 on the front side of the semiconductor drift chamber detector, which shows in detail the connection details between the electrodes on the front side of the detector and the test circuit. Figure 3 This is a flow chart of a semiconductor drift chamber detector testing method based on an optical fiber adjustable probe station of the present invention, through which the testing process of the method of the present invention can be clearly understood. Figure 4 The front and back views of the silicon drift detector used in the example experiment, which include an anode electrode 301 , an innermost drift ring electrode 302 , an outermost drift ring electrode 303 , a guard ring 304 , and a back electrode 305 . Figure 5 This is a schematic diagram of electrode wiring of an exemplary device in the present invention, further detailing the connection method between each electrode and a digital multimeter channel. Figure 6 The figure is a relationship diagram between the outermost drift ring voltage and the anode electrode current of the exemplary device of the present invention, showing the change of the anode electrode 301 current under different illumination positions and the outermost drift ring voltage, providing a data basis for judging the drift characteristics. Figure 6 It can be seen from the figure that under the premise of device longitudinal depletion, as the bias voltage of the outermost drift ring increases from -100 V to -180 V and the illumination position increases from 100 μm to 500 μm from the center, the photocurrent obtained at the device anode electrode 301 gradually increases to 10 -6The current difference at different illumination positions of the A and device gradually becomes smaller. Generally, from the example experiment, we can see that the photocurrents of the device at different positions are almost the same, and the current difference is less than 0.1 uA, which indicates the effective formation of the electron drift effect on the side and proves the feasibility of the design method and system.

[0057] Through the innovative test system design and unique test method of the present invention, the drawbacks of the traditional test method are effectively solved. Compared with the existing integrated test method, there is no need for complex radiation sources, double-sided packaging, and back-end electronics matching circuits. Only through a laser, a double-sided probe station, 4 probes, 2 two-channel digital multimeters, and a novel scanning method, the drift characteristics of the semiconductor drift chamber detector can be quickly verified, greatly shortening the test time and improving the iteration speed of the device, which has remarkable innovation and practicality in the field of semiconductor drift chamber detector testing.

[0058] Based on the description and drawings of the present invention, those skilled in the art can easily manufacture or use a test system for the drift characteristics of a semiconductor drift chamber detector of the present invention and can produce the positive effects recorded in the present invention.

[0059] The above are only the preferred implementation schemes of the present invention, but the present invention is not limited to the above specific implementation schemes. Those of ordinary skill in the art can make several modifications, supplements, or use similar methods for substitution without departing from the principle of the present invention, and these should also be regarded as the protection scope of the present invention.

Claims

1. A test system for drift characteristics of a semiconductor drift chamber detector, characterized in that: The test system comprises: A double-sided probe station (4), wherein a plurality of probes are arranged on the double-sided probe station (4); A semiconductor drift chamber detector (3), the semiconductor drift chamber detector (3) being placed on the double-sided probe station (4) and connected to the probe, and the back side of the semiconductor drift chamber detector (3) being arranged upward; the front side of the semiconductor drift chamber detector (3) comprising an anode electrode (301), an innermost drift ring electrode (302) and an outermost drift ring electrode (303); and the back side of the semiconductor drift chamber detector (3) comprising a back electrode (305); A first dual-channel digital multimeter (5), wherein two channels of the first dual-channel digital multimeter (5) are respectively connected to the innermost drift ring electrode (302) and the back electrode (305) via the probes; A second dual-channel digital multimeter (6), wherein two channels of the second dual-channel digital multimeter (6) are respectively connected to the anode electrode (301) and the outermost drift ring electrode (303) via the probe; the second dual-channel digital multimeter (6) is connected to a computer terminal (7); A laser (1), wherein the laser (1) is connected to an optical fiber (2), and the output end of the optical fiber (2) is used to irradiate the back side of the semiconductor drift chamber detector (3).

2. The semiconductor drift chamber detector drift characteristic testing system according to claim 1, characterized in that: The test system further comprises an optical fiber clamp, which is used to clamp the optical fiber (2) and drive the optical fiber (2) to move in different directions, so as to adjust the irradiation position of the optical fiber (2) on the back side of the semiconductor drift chamber detector (3).

3. The semiconductor drift chamber detector drift characteristic testing system according to claim 1, characterized in that: The laser (1) comprises a laser controller and a laser light source, wherein the laser light source comprises a light source in the ultraviolet light, visible light and near infrared bands.

4. The semiconductor drift chamber detector drift characteristic testing system according to claim 1, characterized in that: The incident path of the optical fiber (2) is perpendicular to the plane of the double-sided probe station (4).

5. The semiconductor drift chamber detector drift characteristic testing system according to claim 1, characterized in that: The first dual-channel digital multimeter (5) and the second dual-channel digital multimeter (6) are connected to a common ground.

6. A method for testing drift characteristics of a semiconductor drift chamber detector, using a system for testing drift characteristics of a semiconductor drift chamber detector according to any one of claims 1 to 5, characterized in that: The test method includes: S1, selecting the wavelength of the laser (1) to be measured and adjusting the output light power of the laser (1); S2, placing the semiconductor drift chamber detector (3) to be tested on a double-sided probe station (4) in a closed darkroom (8), and connecting a first dual-channel digital multimeter (5) and a second dual-channel digital multimeter (6) to the innermost drift ring electrode (302), the back electrode (305), the anode electrode (301), and the outermost drift ring electrode (303) respectively through a plurality of probes; S3, irradiating the optical signal obtained in step S1 to the micro-region on the back side of the semiconductor drift chamber detector (3) via the optical fiber (2); S4, controlling by a first dual-channel digital multimeter (5), respectively outputting a first bias voltage and a second bias voltage on the innermost drift ring electrode (302) and the back electrode (305); controlling by a second dual-channel digital multimeter, fixing the anode electrode (301) at 0V, performing a sweep voltage scan on the outermost drift ring electrode (303), and simultaneously monitoring the anode electrode (301) current signal using a computer terminal (7); S5, by gradually adjusting the different illumination positions of the optical fiber (2), current signals at multiple different illumination positions are obtained; if the current difference at different illumination positions is less than a preset value, the lateral drift characteristic of the semiconductor drift chamber detector (3) is judged to be qualified, and other performance test links are entered; if the current difference at different illumination positions is greater than the preset value, the lateral drift characteristic of the semiconductor drift chamber detector (3) is judged to be unqualified.

7. The method for testing drift characteristics of a semiconductor drift chamber detector according to claim 6, characterized in that: The absolute value of the bias voltage of the back electrode (305) is greater than the absolute value of the longitudinal depletion voltage of the semiconductor drift chamber detector (3), and the bias voltage of the outermost drift ring electrode (303) does not exceed twice the longitudinal depletion voltage of the semiconductor drift chamber detector (3).

8. The method for testing drift characteristics of a semiconductor drift chamber detector according to claim 6, characterized in that: The illumination position of the optical fiber (2) is adjusted in a manner of gradually moving from the center of the semiconductor drift chamber detector (3) to the edge in a radial direction.

9. The method for testing drift characteristics of a semiconductor drift chamber detector according to claim 6, characterized in that: The first bias voltage and the second bias voltage are both negative voltages, the absolute value of the first bias voltage is smaller than the absolute value of the second bias voltage, and the preset value is 0.1uA; the preset current value on the innermost drift ring electrode and the outermost drift ring electrode is 10-50uA.

10. The method for testing drift characteristics of a semiconductor drift chamber detector according to claim 6, characterized in that: In step S4, the voltages of the innermost drift ring electrode and the outermost drift ring electrode are adjusted according to the current signal data collected during the test process, so that a linear drift track can be formed inside the semiconductor drift chamber detector (3).

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