阅读说明：本技术 一种空间带电粒子入射位置及能量探测器和探测方法 (Space charged particle incident position and energy detector and detection method ) 是由 张鑫 孙越强 白超平 张申毅 张斌全 沈国红 朱光武 陈睿 于 2018-08-06 设计创作，主要内容包括：本发明提出一种空间带电粒子入射位置及能量的探测器,所述探测器包括位置探测单元阵列和后端电路分析处理模块；所述位置探测单元阵列在Y方向和X方向上有若干独立的电荷输出通道,每个电荷输出通道用于在空间带电粒子入射后,在入射位置点的Y方向和X方向上输出不同的电流信号；所述后端电路分析处理模块,对若干电荷输出通道输出的电流信号进行采集,将采集到的电流信号转化为差分电压信号,并将此差分电压信号转换为单端信号进行采集,从而得到带电粒子入射位置和能量。本发明的探测器可以实现对空间带电粒子入射位置的探测,甄别FPGA发生的SEU是否由空间带电粒子引起,并对该空间带电粒子的能量进行检测,为在轨排故提供更加明确的数据支持。(The invention provides a detector for the incident position and energy of space charged particles, which comprises a position detection unit array and a back-end circuit analysis processing module; the position detection unit array is provided with a plurality of independent charge output channels in the Y direction and the X direction, and each charge output channel is used for outputting different current signals in the Y direction and the X direction of an incident position point after space charged particles are incident; the back-end circuit analysis processing module collects current signals output by the plurality of charge output channels, converts the collected current signals into differential voltage signals, and converts the differential voltage signals into single-ended signals for collection, so that the incident position and energy of charged particles are obtained. The detector can detect the incident position of the space charged particles, discriminate whether SEU generated by the FPGA is caused by the space charged particles, detect the energy of the space charged particles and provide more definite data support for the track panel.)

1. A detector for the incident position and energy of space charged particles is characterized by comprising a position detection unit array and a back-end circuit analysis processing module;

the position detection unit array is provided with a plurality of independent charge output channels in the Y direction and the X direction, and each charge output channel is used for outputting different current signals in the Y direction and the X direction of an incident position point after space charged particles are incident;

the back-end circuit analysis processing module is used for collecting current signals output by the plurality of charge output channels, converting the collected current signals into differential voltage signals, and converting the differential voltage signals into single-ended signals for collection, so that the incident position and energy of charged particles are obtained.

2. The spatially charged particle incident position and energy detector of claim 1, wherein the array of position detection units comprises: the sensor comprises a first silicon micro-strip sensor and a second silicon micro-strip sensor, wherein the first silicon micro-strip sensor and the second silicon micro-strip sensor respectively comprise a plurality of micro-strip detection units.

3. The spatially charged particle incident position and energy detector of claim 2, wherein the microstrip detection unit comprises a separate charge output channel for outputting a charge pulse.

4. The spatially charged particle incident position and energy detector of claim 3, wherein the number of microstrip detection units of the first silicon microstrip sensor is 6, and the number of microstrip detection units of the second silicon microstrip sensor is the same as that of the first silicon microstrip sensor; a 6x6 array of position-detecting elements each having a size of 2mmx2mm was constructed.

5. The spatially charged particle incident position and energy detector according to claim 4, wherein the first silicon microstrip sensor and the second silicon microstrip sensor are combined in a vertically and horizontally crossing manner; the first silicon microstrip sensor and the second silicon microstrip sensor are tightly attached up and down, wherein the first silicon microstrip sensor is arranged above the second silicon microstrip sensor and used for realizing Y-direction positioning, and the second silicon microstrip sensor is tightly attached to the chip (7) to be tested and used for realizing X-direction positioning; when the charged particles pass through the upper and lower silicon micro-strip sensors, only the position detection unit through which the particles pass has a signal output on any one sensor.

6. The spatially charged particle incident position and energy detector according to claim 5, wherein the back-end circuit analyzing and processing module comprises a charge measuring unit, an analog-to-digital conversion unit and a data processing unit;

the charge measurement unit comprises a special charge measurement chip, and the special charge measurement chip is used for reading out the charge pulse signals output by each microstrip detection unit one by one and outputting the charge pulse signals to the analog-to-digital conversion unit one by one according to the sequence;

the charge pulse signal value output by the micro-strip detection unit through which the charged particles pass is changed, and the charge pulse signal output by the other micro-strip detection units is 0;

the analog-to-digital conversion unit comprises an analog-to-digital converter (ADC) and is used for completing analog-to-digital conversion of 12 paths of detection signals one by one and then outputting the detection data in sequence;

the data processing unit is used for processing and storing the detection data; identifying according to the output sequence of the detection data, and determining the serial number of the micro-strip detection unit where the charged particle incident position is located according to the corresponding sequence number of the detection data which is not 0, so as to determine the incident position; and also for calculating the energy of the incident charged particles from the detection data.

7. A method of detecting the position and energy of incidence of spatially charged particles based on the detector of any of claims 1-6, the method comprising:

step 1) applying high voltage to two ends of the position detection unit array, capturing charges generated by energy deposition in space particles after the space particles are incident, forming charge pulses, and outputting the charge pulses through an output channel of the microstrip detection unit where the incident position is located;

step 2) the charge measurement unit of the back-end circuit analysis processing module scans a plurality of output channels of the position detection unit array one by one and collects the charge pulse signals;

step 3) the charge measurement unit outputs the collected charge pulse signals one by one;

the analog-to-digital conversion unit performs analog-to-digital conversion on the charge pulse signals of each channel to obtain detection data, and the detection data are output to the data processing unit one by one;

step 4), the data processing unit identifies according to the output sequence of the detection data and determines the incident position; the energy of the incident charged particles is calculated from the detected data values.

8. The method according to claim 7, wherein the step 3) comprises:

step 3-1), the charge measuring unit outputs the charge pulse signals of 12 channels one by one to output as differential current signals;

step 3-2) outputting the differential currents of the 12 channels one by one to the same pair of resistor networks, and converting the differential currents one by one into proportional differential voltage signals;

step 3-3) the charge measurement unit amplifies the differential voltage signals of each channel one by one, and converts the amplified differential signals into single-ended analog voltage signals to output one by one;

and 3-4) the ADC collects the single-ended analog voltage signal, converts the single-ended analog voltage signal into a digital voltage signal and outputs the digital voltage signal.

9. The method according to claim 8, wherein the step 4) comprises:

step 4-1) the data processing unit receives the digital voltage signals one by one;

step 4-2) identifying according to the output sequence of the digital voltage signals, determining the serial number of the microstrip detection unit where the charged particle incident position is located according to the serial number corresponding to the digital voltage signal which is not 0, and determining the incident position;

and 4-3) obtaining the number of incident electrons according to the voltage U output by the digital voltage signal:

Q＝U/C (1)

q is the amount of charge, in coulombs; u is voltage, namely detected pulse peak voltage; c is known capacitance, in units of faradays;

step 4-4) calculating the energy value E of the charged particles at the incident point according to the fact that the energy required for generating 1 electron is 3.62 eV:

E＝3.62*Q (2)。

Technical Field

The invention relates to the field of research on a spacecraft and load and space environment effects thereof, in particular to a detector and a detection method for incident positions and energy levels of space charged particles.

Background

Large-scale integrated circuits such as an FPGA, a DSP, and an SOC are widely applied to spacecrafts such as satellites due to their advantages of high performance, abundant resources, and reconfigurability, and these large-scale integrated circuits or systems are susceptible to a single event upset effect (hereinafter abbreviated as SEU). The current method for judging whether the SEU occurs is limited to adopt measures of power-off restarting, refreshing, partial reconstruction and the like after the on-track logic state is changed to observe whether the on-track logic state is recovered, and if the on-track logic state is recovered, the change of the logic state is judged to be caused by the SEU. However, it is less studied whether such an abnormality is caused by high-energy charged particles like a change in logic state, and information on the occurrence position of SEU. This may result in inaccurate use of circuit or system repair measures, which may affect stable implementation of the on-orbit performance of the spacecraft, or even may endanger the on-orbit safety of the spacecraft. Therefore, the research on the on-orbit SEU screening and positioning technology of the spacecraft needs to be carried out, faults caused by the on-orbit SEU are screened, position information of the on-orbit SEU is acquired, and technical support is provided for timely and accurately taking countermeasures.

In a common spatial SEU effect research, a detector is generally placed beside a detected FPGA, the probability of SEU occurrence of the FPGA is evaluated through information such as particle flux, energy spectrum and the like detected by the detector, and the relation between single particle incidence and single particle upset events is difficult to determine jointly in space and time.

Disclosure of Invention

The invention aims to solve the problems that the on-orbit performance of a spacecraft is influenced and even the on-orbit safety of the spacecraft is endangered due to the fact that the circuit or system repair measures are not accurate enough because the position of the SEU cannot be determined and whether high-energy particles bombard the concerned large-scale integrated circuit for the satellite cannot be accurately judged.

In order to achieve the purpose, the invention provides a space charged particle incident position, an energy detector and a detection method according to the working conditions of a semiconductor detector and the requirements of position sensitive detection, and the detection of the space charged particle incident position is achieved.

The detector comprises a position detection unit array and a back-end circuit analysis processing module;

the position detection unit array is provided with a plurality of independent charge output channels in the Y direction and the X direction, and each charge output channel is used for outputting different current signals in the Y direction and the X direction of the position of an incident position after space charged particles are incident;

the back-end circuit analysis processing module is used for collecting current signals output by the plurality of charge output channels, converting the collected current signals into differential voltage signals, and converting the differential voltage signals into single-ended signals for collection, so that the incident position and energy of charged particles are obtained.

As an improvement of the above apparatus, the position detection unit array includes: the sensor comprises a first silicon micro-strip sensor and a second silicon micro-strip sensor, wherein the first silicon micro-strip sensor and the second silicon micro-strip sensor respectively comprise a plurality of micro-strip detection units.

As an improvement of the device, the microstrip detection unit comprises an independent charge output channel for outputting charge pulses.

As an improvement of the above device, the number of microstrip detection units of the first silicon microstrip sensor is 6, and the number of microstrip detection units of the second silicon microstrip sensor is the same as that of the first silicon microstrip sensor; the first silicon micro-strip sensor and the second silicon micro-strip sensor constitute a 6x6 array of position detecting units, each having a size of 2mmx2 mm.

As an improvement of the device, the first silicon micro-strip sensor and the second silicon micro-strip sensor are combined in a vertical, horizontal and vertical crossing mode; the first silicon microstrip sensor and the second silicon microstrip sensor are tightly attached up and down, wherein the first silicon microstrip sensor is arranged above the second silicon microstrip sensor and used for realizing Y-direction positioning, and the second silicon microstrip sensor is tightly attached to the tested chip 7 and used for realizing X-direction positioning; when charged particles pass through the upper silicon micro-strip sensor and the lower silicon micro-strip sensor, only the micro-strip detection unit through which the particles pass has signal output on any one sensor.

As an improvement of the above device, the back-end circuit analysis processing module includes a charge measuring unit, an analog-to-digital conversion unit and a data processing unit;

the charge measurement unit comprises a special charge measurement chip, and the special charge measurement chip is used for reading out the charge pulse signals output by each microstrip detection unit one by one and outputting the charge pulse signals to the analog-to-digital conversion unit one by one according to the sequence;

the charge pulse signal value output by the micro-strip detection unit through which the charged particles pass is changed, and the charge pulse signal output by the other micro-strip detection units is 0;

the analog-to-digital conversion unit comprises an analog-to-digital converter (ADC) and is used for completing analog-to-digital conversion of 12 paths of detection signals one by one and then outputting the detection data in sequence;

the data processing unit is used for processing and storing the detection data; identifying according to the output sequence of the detection data, and determining the serial number of the micro-strip detection unit where the charged particle incident position is located according to the corresponding sequence number of the detection data which is not 0, so as to determine the incident position; and also for calculating the energy of the incident charged particles from the detection data.

The invention also provides a detection method of the incident position and the energy of the space charged particles based on the detector, and the method comprises the following steps:

step 1) applying high voltage to two ends of the position detection unit array, capturing charges generated by energy deposition in space particles after the space particles are incident, forming charge pulses, and outputting the charge pulses through an output channel of the microstrip detection unit where the incident position is located;

step 2) the charge measurement unit of the back-end circuit analysis processing module scans a plurality of output channels of the position detection unit array one by one and collects the charge pulse signals;

step 3) the charge measurement unit outputs the collected charge pulse signals one by one;

the analog-to-digital conversion unit performs analog-to-digital conversion on the charge pulse signals of each channel to obtain detection data, and the detection data are output to the data processing unit one by one;

step 4), the data processing unit identifies according to the output sequence of the detection data and determines the incident position; the energy of the incident charged particles is calculated from the detected data values.

As a modification of the above method, the step 3) includes:

step 3-1), the charge measuring unit outputs the charge pulse signals of 12 channels one by one to output as differential current signals;

step 3-2) outputting the differential currents of the 12 channels one by one to the same pair of resistor networks, and converting the differential currents one by one into proportional differential voltage signals;

step 3-3) the charge measurement unit amplifies the differential voltage signals of each channel one by one, and converts the amplified differential signals into single-ended analog voltage signals to output one by one;

and 3-4) the ADC collects the single-ended analog voltage signal, converts the single-ended analog voltage signal into a digital voltage signal and outputs the digital voltage signal.

As a modification of the above method, the step 4) includes:

step 4-1) the data processing unit receives the digital voltage signals one by one;

step 4-2) identifying according to the output sequence of the digital voltage signals, determining the serial number of the microstrip detection unit where the charged particle incident position is located according to the corresponding serial number of the charge pulse signal which is not 0, and determining the incident position;

and 4-3) obtaining the number of incident electrons according to the voltage U output by the digital voltage signal:

Q＝U/C (1)

q is the amount of charge, in coulombs; u is voltage, namely detected pulse peak voltage; c is known capacitance, in units of faradays;

step 4-4) calculating the energy value E of the charged particles at the incident point according to the fact that the energy required for generating 1 electron is 3.62 eV:

E＝3.62*Q (2)

the invention has the advantages that: the detector can detect the incident position of the space charged particles, discriminate whether SEU generated by the FPGA is caused by the space charged particles, detect the energy of the space charged particles and provide more definite data support for the track panel.

Drawings

FIG. 1(a) is a diagram of a first silicon micro-strip sensor structure of the probe of the present invention;

FIG. 1(b) is a diagram of a second silicon micro-strip sensor structure of the probe of the present invention;

FIG. 2 is an exploded view of the spatial charged particle incident position and energy detector configuration of the detector of the present invention;

FIG. 3 is a schematic diagram of the structure of the detector for detecting the incident position of the spatially charged particles and the energy of the detector according to the present invention;

FIG. 4 is a schematic diagram of a detection method of the present invention;

fig. 5 is a schematic diagram of the incident charged particle energy measurement according to the present invention.

The attached drawings are as follows:

1. first silicon microstrip sensor 2, second silicon microstrip sensor

3. First preamplifier board 4, second preamplifier board

5. Inter-board connector 6 and signal adapter plate

7. Chip to be tested

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments.

The invention adopts a research mode different from the traditional single event effect, and the semiconductor sensor is arranged above the FPGA (the chip 7 to be tested), so that the energy spectrum of the particles incident on the FPGA can be monitored, and the research on the relevance of the SEU and the high-energy particles of a specific circuit system is realized.

As shown in fig. 1(a) and 1(b), a spatial charged particle incident position and energy detector of the present invention is composed of 2 silicon microstrip sensors and a back-end circuit analysis processing module, wherein each silicon microstrip sensor has 6 silicon microstrip detection units (12mm × 2 mm). The two silicon micro-strip sensors form a 6x6 position detection unit array in a vertical, horizontal and vertical crossing mode, the size of each position detection unit is 2mmx2mm, and each position detection unit can independently output signals.

As shown in fig. 2 and 3, the overall structure of the detector includes two silicon micro-strip sensors: the device comprises a first silicon microstrip sensor and a second silicon microstrip sensor, wherein the first silicon microstrip sensor is arranged on the second silicon microstrip sensor to realize Y-direction positioning, and the second silicon microstrip sensor is tightly attached to a chip FPGA to be tested to realize X-direction positioning.

In the engineering practice, the sensors with smaller microstrip width and more columns are selected, the distance between the upper silicon microstrip sensor and the lower silicon microstrip sensor is as small as possible, and the position resolution can be further improved; the silicon microstrip sensors can be customized, the distance between the two silicon microstrip sensors is further reduced, and calculation errors caused by incident particles are reduced.

The principle of the invention is that due to the ionization effect of the space charged particle radiation, electron-hole pairs are formed inside the silicon micro-strip sensors, and the electron-hole pairs are collected to the output end of the sensors under the action of high-voltage electric fields inside the first silicon micro-strip sensor and the second silicon micro-strip sensor and generate charge output signals. The charge signal can be analyzed and processed by the back end circuit to obtain particle deposition energy information, and the LET spectrum of the radiation particles can be calculated and obtained by combining the thickness of the sensor and the particle incidence direction information. And meanwhile, the first silicon microstrip sensor and the second silicon microstrip sensor are combined to respectively obtain output current signals in the Y direction and the X direction for distinguishing the particle incidence positions. When charged particles pass through the upper silicon micro-strip sensor and the lower silicon micro-strip sensor, only the position detection unit through which the particles pass has signal output on any sensor, and other micro-strips have no signal output, and position identification can be realized by detecting the signal and judging the serial number of the micro-strip where the signal is located; position sensitive detection is achieved.

The back-end circuit analysis processing module comprises a charge measuring unit, an analog-to-digital conversion unit and a data processing unit.

Because the number of output circuits of the silicon microstrip sensor is large, a VA32ASIC (hereinafter referred to as VA32) which is a multi-channel and high-integration special charge measurement chip widely used in the aerospace field is adopted to realize charge measurement.

The charge measuring unit comprises 1 VA32, the reading of detector signals of 12 channels is realized, the output of the VA32 is controlled externally, only one output is enabled to be effective at the same time, and the rest are in a high-impedance state; the 12 paths of output of the VA32 can be controlled to be output one by one according to requirements, and when one path of output is output, other paths keep high impedance. The output charge signals are effective, and the serial number of the microstrip detection unit where the incident and emergent positions are located can be identified according to the output charge signals; thereby realizing the identification of the position;

the analog-to-digital conversion unit adopts a piece of analog-to-digital converter ADC, and can complete analog-to-digital conversion of 12 paths of signals.

As shown in fig. 4, the present invention further includes a method for detecting an incident position of spatially charged particles, the method being based on the following principle: after the space particles are incident to the position detection unit array, energy is deposited inside the space particles to generate charges, and the charges are captured by high voltage at two ends of the first silicon micro-strip sensor and the second silicon micro-strip sensor to form charge pulses.

The ionization energy of the silicon semiconductor is 3.62eV, that is, a charged particle with energy of 3.62eV is incident into the silicon semiconductor and is completely deposited, an electron is excited, that is, energy of 3.62eV is consumed for generating one electron.

As shown in fig. 5, when charged particles are injected into a silicon semiconductor and a large amount of charges are generated, the charges are collected by a capacitor with a known capacity to form a pulse, the peak value of the pulse is detected by a back-end circuit, and then how many electrons are present is known, and how much energy is present is reversely deduced.

Q＝U/C(1)

Q: the amount of charge, coulomb; u: voltage, i.e., the detected pulse peak voltage; c: capacitance, faraday, known quantity;

from the above equation, Q can be found, and then from the 3.62eV energy required to generate 1 electron, the energy value E can be found:

E＝3.62*Q(2)。

the method comprises the steps that measurement of charge pulses and detection of an incident position are completed through a back-end circuit analysis processing module, wherein the back-end circuit analysis processing module comprises a charge measuring unit, an analog-to-digital conversion unit and a data processing unit;

since the VA32 outputs a differential current signal, it needs to be converted into a voltage signal. The specific method of current-voltage (I-V) signal conversion is to connect the differential current output of VA32 to the same pair of resistor networks, convert it to a proportional voltage signal, then transmit the differential voltage signal to an analog conditioning circuit for amplification, and convert the differential signal to a single-ended signal for sampling by the analog-to-digital converter ADC. And finally, transmitting the acquired data to a data processing unit for processing and storing to obtain the incident position and the energy level of the particle.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.