A self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector

Abstract

The present invention discloses a self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector, which belongs to the field of semiconductor technology and includes the following steps: performing a variable temperature turn-on voltage experiment on the PIN semiconductor detector to obtain the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector; obtaining the magnitude of the forward turn-on voltage applied to the PIN semiconductor detector in real time; determining the current operating temperature of the PIN semiconductor detector according to the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector, and calculating and determining the magnitude of the reverse dark current of the current PIN semiconductor detector; and calibrating the signal current of the PIN semiconductor detector according to the magnitude of the reverse dark current obtained by calculation. The present invention can realize the internal operating temperature self-detection of the PIN semiconductor detector without an external temperature detection module, simplifies the detection system, and increases the system reliability.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to a self-calibration measurement method for a turn-on voltage of a PIN semiconductor detector. Background Art

[0002] In the field of radiation detection, PIN semiconductor radiation detectors will experience temperature changes during operation due to heat transfer from the external environment, nuclear reactions between the radiation source and the detector material, and application of an external power supply. When performing radiation detection in a low-temperature environment, the temperature change of the PIN semiconductor radiation detector has a significant impact on the accuracy of the detector signal current. Specifically, when the operating temperature of the PIN semiconductor radiation detector increases, the reverse dark current inside the PIN semiconductor radiation detector increases.

[0003] When performing radiation detection, the PIN semiconductor radiation detector needs to operate under a reverse operating voltage. Radiation particles cause ionization reactions inside the PIN semiconductor radiation detector, generating electron-hole pairs. Under the reverse operating voltage, the electron-hole pairs flow in a directed manner, thereby generating a signal current. However, when the PIN semiconductor detector is not irradiated, it will still generate a reverse dark current due to the thermal excitation effect and the applied operating voltage. The reverse dark current will be superimposed on the signal current, affecting the signal accuracy of the PIN semiconductor radiation detector. The higher the operating temperature of the PIN semiconductor radiation detector, the greater the reverse dark current and the greater the interference to the signal. Therefore, it is necessary to detect the real-time temperature of the PIN semiconductor radiation detector when it is working in order to calculate the real-time reverse dark current, thereby realizing the calibration of the signal current.

[0004] At present, the temperature detection method for PIN semiconductor radiation detectors is usually infrared temperature detection or thermocouple: for infrared temperature detection system, the measured temperature is the surface temperature of the detector; for thermocouple system, the measured temperature is related to the current of the circuit where the detector is located. Both of these temperature detection methods have the problem that they cannot directly realize the internal working temperature detection of the detector and add additional large modules to the detection system, resulting in reduced system reliability. In extreme low-temperature working environments, the requirements for accurate detection of the working temperature of PIN semiconductor radiation detectors and the reliability of the detection system are further improved. Therefore, it is necessary to use the existing electrical parameters of the detection system to realize self-detection of the working temperature of the PIN semiconductor radiation detector and self-calibration of the signal current of the PIN semiconductor radiation detector. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector with simple algorithm and high measurement accuracy.

[0006] The technical solution of the present invention to solve the above technical problem is: a self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector, comprising the following steps:

[0007] S1: Conduct a variable temperature turn-on voltage experiment on the PIN semiconductor detector to obtain the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector;

[0008] S2: Real-time acquisition of the forward turn-on voltage applied to the PIN semiconductor detector;

[0009] S3: determining the current operating temperature of the PIN semiconductor detector according to the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector, and calculating and determining the magnitude of the reverse dark current of the current PIN semiconductor detector;

[0010] S4: Calibrate the signal current of the PIN semiconductor detector according to the calculated reverse dark current.

[0011] The self-calibration measurement method of the turn-on voltage of the PIN semiconductor detector is implemented based on a measurement system, and the measurement system includes:

[0012] A PIN semiconductor detector, wherein the PIN semiconductor detector is a PIN junction diode structure, and a signal pin of the PIN semiconductor detector is connected to a driving system;

[0013] A driving system, the driving system provides a forward and reverse working voltage of the PIN semiconductor detector and detects the working voltage and uncalibrated signal current of the PIN semiconductor detector;

[0014] A processor stores the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector and the calculation program of the reverse dark current and the operating temperature of the PIN semiconductor detector. The processor calculates the operating temperature and the operating reverse dark current of the PIN semiconductor detector in real time, and calibrates and outputs the signal current of the PIN semiconductor detector according to the operating reverse dark current in real time.

[0015] In the self-calibration measurement method of the turn-on voltage of the above-mentioned PIN semiconductor detector, in the step S1, in the variable temperature turn-on voltage experiment, the PIN semiconductor detector to be tested needs to be placed on a solid heating table and connected to the current test circuit. In a single test, the voltage source in the circuit is gradually increased; when the PIN semiconductor detector is turned on, its signal current will increase sharply. In a single test, it is ensured that the turn-on phenomenon is observed, and the forward current density of the PIN semiconductor detector after it is turned on is recorded. ; Change the temperature of the solid heating stage , and repeatedly record the forward current density of the PIN semiconductor detector at different temperatures Depending on the voltage source size Changes in situation.

[0016] In the self-calibration measurement method for the turn-on voltage of the PIN semiconductor detector, in step S1, the experiment is performed multiple times to obtain at least five PIN semiconductor detector turn-on phenomena. - Change curve.

[0017] The self-calibration measurement method for the turn-on voltage of the PIN semiconductor detector mentioned above, in step S1, the material information of the PIN semiconductor detector is obtained by querying the manual provided by the manufacturer, and the intrinsic carrier concentration of the PIN semiconductor detector to be measured is obtained. , drift zone half width , bipolar diffusion coefficient , the following formula is used to calculate the PIN semiconductor detector at different operating temperatures The opening voltage :

[0018]

[0019]

[0020]

[0021]

[0022] Where: is the basic charge; is the Boltzmann coefficient; is the voltage drop in the drift region of the PIN semiconductor detector; is the bipolar diffusion length; is the majority carrier lifetime of PIN semiconductor detector; is an intermediate quantity, tanh is the hyperbolic tangent function;

[0023] Calculate the turn-on voltage of the PIN semiconductor detector to be tested With the working temperature T data, linear fitting is performed to obtain (T) function, and enter the function into the processor of the measurement system.

[0024] The self-calibration measurement method for the turn-on voltage of the PIN semiconductor detector described above, in step S3, during the operation of the PIN semiconductor radiation detector, the reverse dark current The relationship with the real-time operating temperature is calculated by the following formula:

[0025]

[0026] Where: is the diffusion coefficient of the n-region of the PIN semiconductor detector, is the diffusion coefficient of the p-region of the PIN semiconductor detector; is the diffusion length of the n region of the PIN semiconductor detector, is the diffusion length of the p-region of the PIN semiconductor detector; is the acceptor doping concentration of the PIN semiconductor detector, is the donor doping concentration of PIN semiconductor detector.

[0027] In the self-calibration measurement method for the turn-on voltage of the PIN semiconductor detector, in step S1, the variable temperature turn-on voltage experiment is carried out in a light-proof, constant temperature and room pressure environment.

[0028] The beneficial effects of the present invention are:

[0029] 1. The present invention obtains the linear correspondence between the operating temperature and the forward turn-on voltage of the PIN semiconductor radiation detector. The correspondence is related to the material performance of the PIN semiconductor radiation detector and can be obtained through a variable temperature turn-on voltage experimental test. The operating temperature of the PIN semiconductor detector can be directly obtained based on the relationship. The present invention can realize the internal operating temperature self-detection of the PIN semiconductor detector without an external temperature detection module, simplifying the detection system and increasing the system reliability.

[0030] 2. The present invention improves the measurement accuracy of the PIN semiconductor radiation detector, reduces the measurement error of the operating temperature of the PIN semiconductor detector, and reduces the reverse dark current error of the PIN semiconductor detector calculated from the operating temperature, thereby reducing the error of the measurement system after calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a flow chart of the present invention.

[0032] Figure 2 This is a schematic diagram of the measurement system circuit used in the present invention.

[0033] In the figure, 1 is a PIN semiconductor detector, 2 is a processor, 3 is a first power supply, 4 is a second power supply, 5 is a current measuring device, and 6 is a voltage measuring device. DETAILED DESCRIPTION

[0034] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0035] like Figure 1 As shown, a self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector comprises the following steps:

[0036] S1: Perform a variable temperature turn-on voltage experiment on the PIN semiconductor detector to obtain the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector.

[0037] Since the signal current of the PIN semiconductor radiation detector will be disturbed by the reverse dark current, and the magnitude of the reverse dark current is related to the operating temperature of the PIN semiconductor radiation detector, the relationship between the operating temperature and the turn-on voltage of the PIN semiconductor radiation detector can be characterized by a variable temperature turn-on voltage experiment, thereby judging the real-time operating temperature and reverse dark current by the turn-on voltage of the PIN semiconductor radiation detector when it is working.

[0038] To avoid interference from the surrounding environment, the variable temperature turn-on voltage experiment is carried out in a light-proof, constant temperature, and room pressure environment. In the variable temperature turn-on voltage experiment, the PIN semiconductor detector to be tested needs to be placed on a solid heating table and connected to the current test circuit. In a single test, the voltage source in the circuit is gradually increased; when the PIN semiconductor detector is turned on, its signal current will increase sharply. In a single test, the turn-on phenomenon is guaranteed to be observed, and the forward current density of the PIN semiconductor detector after it is turned on is recorded. ; Change the temperature of the solid heating stage , and repeatedly record the forward current density of the PIN semiconductor detector at different temperatures Depending on the voltage source size The experiment was carried out several times to obtain at least five traces containing the PIN semiconductor detector opening phenomenon. - Change curve.

[0039] Consult the manual provided by the manufacturer to obtain the material information of the PIN semiconductor detector and the intrinsic carrier concentration of the PIN semiconductor detector to be tested. , drift zone half width , bipolar diffusion coefficient , the following formula is used to calculate the PIN semiconductor detector at different operating temperatures The opening voltage :

[0040]

[0041]

[0042]

[0043]

[0044] Where: is the basic charge; is the Boltzmann coefficient; is the voltage drop in the drift region of the PIN semiconductor detector; is the bipolar diffusion length; is the majority carrier lifetime of PIN semiconductor detector; is an intermediate quantity, tanh is the hyperbolic tangent function;

[0045] Calculate the turn-on voltage of the PIN semiconductor detector to be tested With the working temperature T data, linear fitting is performed to obtain (T) function, and enter the function into the processor of the measurement system.

[0046] S2: Obtain the forward turn-on voltage applied to the PIN semiconductor detector in real time.

[0047] S3: According to the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector, the current operating temperature of the PIN semiconductor detector is determined, and the reverse dark current of the current PIN semiconductor detector is calculated and determined.

[0048] During the operation of the PIN semiconductor radiation detector, the reverse dark current The relationship with the real-time operating temperature is calculated by the following formula:

[0049]

[0050] Where: is the diffusion coefficient of the n-region of the PIN semiconductor detector, is the diffusion coefficient of the p-region of the PIN semiconductor detector; is the diffusion length of the n region of the PIN semiconductor detector, is the diffusion length of the p-region of the PIN semiconductor detector; is the acceptor doping concentration of the PIN semiconductor detector, is the donor doping concentration of PIN semiconductor detector.

[0051] S4: Calibrate the signal current of the PIN semiconductor detector according to the calculated reverse dark current.

[0052] The self-calibration measurement method of the turn-on voltage of the PIN semiconductor detector is implemented based on the measurement system, such as Figure 2 As shown, the measurement system comprises:

[0053] A PIN semiconductor detector 1, wherein the PIN semiconductor detector 1 is a PIN junction diode structure, and a signal pin of the PIN semiconductor detector 1 is connected to a driving system;

[0054] A driving system, the driving system provides a forward and reverse working voltage of the PIN semiconductor detector and detects the working voltage and uncalibrated signal current of the PIN semiconductor detector;

[0055] Processor 2, in which the corresponding relationship between the working temperature and the forward turn-on voltage of the PIN semiconductor detector and the calculation program of the reverse dark current and the working temperature of the PIN semiconductor detector 1 are stored, the processor 2 calculates the working temperature and the working reverse dark current of the PIN semiconductor detector 1 in real time, and calibrates and outputs the signal current of the PIN semiconductor detector 1 according to the working reverse dark current in real time;

[0056] A first power source 3 and a second power source 4 in opposite directions are used to provide power; a current measuring device 5 is used to measure current; and a voltage measuring device 6 is used to measure voltage.

Claims

1. A self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector, characterized in that: The following steps are involved: S1: Conduct a variable temperature turn-on voltage experiment on the PIN semiconductor detector to obtain the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector; In step S1, the material information of the PIN semiconductor detector is obtained by consulting the manual provided by the manufacturer, and the intrinsic carrier concentration n of the PIN semiconductor detector to be tested is obtained. i , drift region half width d, bipolar diffusion coefficient D a , the turn-on voltage V of the PIN semiconductor detector at different operating temperatures T is calculated by the following formula: ON : Where: q is the basic charge; k is the Boltzmann coefficient; V M is the voltage drop in the drift region of the PIN semiconductor detector; L a is the bipolar diffusion length; τ HL is the majority carrier lifetime of the PIN semiconductor detector; F(d / L a ) is an intermediate quantity, tanh is the hyperbolic tangent function; Calculate the turn-on voltage V of the PIN semiconductor detector to be tested ON With the working temperature T data, linear fitting is performed to obtain V ON (T) function, which can be entered into the processor of the measurement system; S2: Real-time acquisition of the forward turn-on voltage applied to the PIN semiconductor detector; S3: determining the current operating temperature of the PIN semiconductor detector according to the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector, and calculating and determining the magnitude of the reverse dark current of the current PIN semiconductor detector; In step S3, during the operation of the PIN semiconductor radiation detector, the reverse dark current J L The relationship with the real-time operating temperature is calculated by the following formula: Where: D n is the diffusion coefficient of the n-region of the PIN semiconductor detector, D p is the diffusion coefficient of the p-region of the PIN semiconductor detector; L n is the diffusion length of the n region of the PIN semiconductor detector, L p N is the diffusion length of the p-region of the PIN semiconductor detector; A is the acceptor doping concentration of the PIN semiconductor detector, N D is the donor doping concentration of the PIN semiconductor detector; S4: Calibrate the signal current of the PIN semiconductor detector according to the calculated reverse dark current.

2. The self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector according to claim 1, characterized in that: The measurement system is implemented based on the measurement system, which includes: A PIN semiconductor detector, wherein the PIN semiconductor detector is a PIN junction diode structure, and a signal pin of the PIN semiconductor detector is connected to a driving system; A driving system, the driving system provides a forward and reverse working voltage of the PIN semiconductor detector and detects the working voltage and uncalibrated signal current of the PIN semiconductor detector; A processor stores the corresponding relationship between the operating temperature and the forward turn-on voltage of the PIN semiconductor detector and the calculation program of the reverse dark current and the operating temperature of the PIN semiconductor detector. The processor calculates the operating temperature and the operating reverse dark current of the PIN semiconductor detector in real time, and calibrates and outputs the signal current of the PIN semiconductor detector according to the operating reverse dark current in real time.

3. The self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector according to claim 2, characterized in that: In the step S1, in the variable temperature turn-on voltage experiment, the PIN semiconductor detector to be tested needs to be placed on a solid heating table and connected to a current test circuit. In a single test, the voltage source in the circuit is gradually increased; when the PIN semiconductor detector is turned on, its signal current will increase sharply. In a single test, it is ensured that the turn-on phenomenon is observed, and the forward current density J of the PIN semiconductor detector after it is turned on is recorded. T ; Change the temperature T of the solid heating stage and repeatedly record the forward current density J of the PIN semiconductor detector at different temperatures T Changes with the voltage source size V.

4. The self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector according to claim 3, characterized in that: In step S1, the experiment is performed multiple times to obtain at least five J containing the PIN semiconductor detector opening phenomenon. T -V change curve.

5. The self-calibration measurement method for the turn-on voltage of a PIN semiconductor detector according to claim 1, characterized in that: In step S1, in order to avoid interference from the surrounding environment, the variable temperature start-up voltage experiment is carried out in a light-proof, constant temperature and room pressure environment.

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