Extremely deep energy level trap detection method and device

Abstract

The invention discloses a detection method and device for an extremely deep energy level trap, and the method comprises the steps: detecting the concentration of the shallow energy level trap of an original to-be-detected semiconductor based on a deep energy level transient spectrum method; according to the nth electron beam filling dose, performing nth electron injection on the to-be-detected semiconductor so as to fill at least one electron in each defect of the to-be-detected semiconductor after (n-1) th injection, and obtaining the to-be-detected semiconductor after nth injection; detecting the concentration of the shallowest energy level trap of the to-be-detected semiconductor after the nth injection based on a deep energy level transient spectrum method to obtain the concentration of the (n + 1) th energy level trap of the original to-be-detected semiconductor; after electron injection is carried out on the deeper energy level trap, the deeper energy level trap can be converted into a shallower energy level trap. According to the invention, the detection of the trap concentration of the deeper energy level can be realized, and the application range is wide.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor technology, and in particular relates to a method and a device for detecting an extremely deep energy level trap. Background Art

[0002] As traps in semiconductor devices have become an important bottleneck restricting the development of semiconductors, various methods for quantitatively characterizing trap characteristics have been proposed. The current mainstream quantitative trap detection method is Deep Level Transient Spectroscopy (DLTS), but it can only detect traps at shallower energy levels, such as traps whose energy levels differ from the bottom of the conduction band or the top of the valence band by less than 1.0 eV, and cannot detect deep energy level traps whose energy levels are close to the midline of the bandgap. If only shallow energy level traps are detected, the impact of deep energy level traps on device characteristics will be ignored, which may mislead the reasons for poor device characteristics or poor reliability. Another popular method is deep energy level spectroscopy, which can only detect photosensitive traps, and has extremely high requirements for laser light source equipment and sample electrodes during detection, and is not universal.

[0003] Therefore, the currently popular trap detection methods are limited in the types of traps they can detect and have a narrow scope of application. Summary of the invention

[0004] The embodiments of the present invention provide a method and device for detecting extremely deep energy level traps, which can solve the problem that currently popular trap detection methods are limited in the types of traps that can be detected and have a narrow scope of application.

[0005] In a first aspect, an embodiment of the present invention provides a method for detecting a very deep energy level trap, the method comprising:

[0006] Based on deep level transient spectroscopy, the concentration of the shallowest energy level traps in the original semiconductor to be tested is detected;

[0007] According to the nth electron beam filling dose, the semiconductor to be tested is subjected to the nth electron injection to fill at least one electron in each defect of the semiconductor to be tested after the n-1th injection, to obtain the semiconductor to be tested after the nth injection, wherein the semiconductor to be tested after the 0th injection is the original semiconductor to be tested, n is a positive integer less than or equal to N-1, and N is the maximum number of energy levels of the same defect in the original semiconductor to be tested;

[0008] Based on the deep energy level transient spectroscopy, the concentration of the shallowest energy level trap of the semiconductor to be tested after the nth injection is detected, and the concentration of the n+1th shallow energy level trap of the original semiconductor to be tested is obtained;

[0009] Among them, after electron injection into the deeper energy level trap, the deeper energy level trap can be converted into a shallower energy level trap.

[0010] In a second aspect, an embodiment of the present invention provides a detection device for extremely deep energy level traps, comprising:

[0011] A deep energy level transient spectrum detection module, which is used to detect the concentration of the shallowest energy level traps of the original semiconductor to be tested based on the deep energy level transient spectrum method;

[0012] An electron injection module, the electron injection module is used to perform an nth electron injection on the semiconductor to be tested according to the nth electron beam filling dose to fill at least one electron in each defect of the semiconductor to be tested after the n-1th injection, to obtain the semiconductor to be tested after the nth injection, wherein the semiconductor to be tested after the 0th injection is the original semiconductor to be tested, n is a positive integer less than or equal to N-1, and N is the maximum number of energy levels of the same defect in the original semiconductor to be tested;

[0013] The deep energy level transient spectrum detection module is also used to detect the concentration of the shallowest energy level trap of the semiconductor to be tested after the nth injection based on the deep energy level transient spectrum method, and obtain the concentration of the n+1th shallow energy level trap of the original semiconductor to be tested;

[0014] Among them, after electron injection into the deeper energy level trap, the deeper energy level trap can be converted into a shallower energy level trap.

[0015] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: according to the method provided by the present invention, by injecting electrons into the semiconductor to be tested, defects at deeper energy levels can be converted into defects at shallower energy levels, and then the injected semiconductor to be tested is detected using the DLTS method to obtain the trap concentration at deeper energy levels, thereby realizing the detection of the trap concentration at deeper energy levels and expanding the detection range; since the present invention does not adopt the deep energy level spectroscopy method, it can realize the detection of semiconductor devices that are insensitive to light excitation and non-transparent semiconductor devices, and there is no need to use lasers; therefore, the present invention has a wider scope of application. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram showing that the formation energy of a trap varies with the energy level provided by an embodiment of the present invention;

[0017] Figure 2 A flowchart of a method for detecting a very deep energy level trap provided by an embodiment of the present invention;

[0018] Figure 3 A schematic structural diagram of a detection device for extremely deep energy level traps provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0020] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0021] It should also be understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0022] As used in the present specification and the appended claims, the term "if" may be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" may be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]", depending on the context.

[0023] In addition, in the description of the present specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0024] References to "one embodiment" or "some embodiments" etc. described in the present specification mean that one or more embodiments of the present invention include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0025] The conventional DLTS method can detect the concentration of semiconductor traps through the following steps S101-S104:

[0026] S101, placing the semiconductor device to be tested into the variable temperature sample chamber, connecting the electrodes of the testing equipment, ensuring the transmission of the electrical signal and evacuating the sample in the chamber.

[0027] S102, set appropriate temperature and test parameters, such as bias voltage V measure , fill voltage V full , Fill pulse width t p , and then apply a test bias voltage to the semiconductor device to be tested. After stabilization, apply a fill pulse voltage to the device, restore the test bias voltage after the pulse ends, and then detect the transient change curve of the capacitance of the semiconductor device to be tested.

[0028] S103, changing the temperature, repeating the above step S102, and obtaining the capacitance transient curves under different temperatures and different rate windows.

[0029] S104, analyzing the capacitance transient curve to obtain the deep energy level transient spectrum of the semiconductor device to be tested, and obtaining the Allenius curve of the semiconductor device to be tested according to the height of the deep energy level transient spectrum and the peak temperature under different rate windows. Then, analyzing the Allenius curve to obtain the trap concentration of the semiconductor device to be tested.

[0030] The traditional DLTS method can only detect shallow energy level traps with energy levels less than 1eV, but cannot detect extremely deep energy level traps with energy levels greater than 1eV or even close to the midline of the semiconductor bandgap.

[0031] Another conventional trap detection method, namely deep level spectroscopy, can detect the concentration of semiconductor traps through the following steps S201-S206:

[0032] S201, placing the semiconductor device to be tested into a variable temperature sample chamber, connecting the electrodes of the testing equipment, ensuring the transmission of the electrical signal and evacuating the sample in the chamber.

[0033] S202, connecting a light excitation source (such as a laser and a xenon lamp) and an electrical measuring device (such as a lock-in amplifier, a signal acquisition system, etc.).

[0034] S203, maintaining a constant temperature of the semiconductor device to be tested by a heating and / or cooling system.

[0035] S204, select a laser light source with an appropriate wavelength to excite the sample, wherein the wavelength of the light source is usually selected to be below the band gap energy of the semiconductor device material to be tested, so as to ensure that the transition of the deep energy level can be excited instead of directly stimulating the transition of the conduction band.

[0036] S205, after the semiconductor device to be tested is excited by light, a highly sensitive device such as a lock-in amplifier is used to measure the conductivity change of the semiconductor to be tested; or the capacitance change of the semiconductor is measured. The conductivity change and the capacitance change can reflect the coincidence or emission process of the deep energy level defect state of the semiconductor device to be tested.

[0037] S206, changing the wavelength of the light source and repeating the above steps S204 and S205 to obtain data corresponding to each wavelength to generate a deep energy level spectrum. Perform fitting analysis on the spectrum to extract the concentration of traps in the semiconductor device to be tested.

[0038] This method can only detect traps that are sensitive to light, but not traps that are insensitive to light excitation. In addition, this method requires the wavelength of the laser light source to be below the bandgap energy of the semiconductor material. For example, to test ultra-wide bandgap semiconductor devices such as gallium oxide, a deep ultraviolet laser with a wavelength less than 253nm is required, and it is extremely difficult to implement lasers in this band. At the same time, since this method requires the laser to penetrate the device for detection, if the device electrode cannot transmit light, the technology cannot be used.

[0039] Therefore, the currently popular trap detection methods are limited in the types of traps they can detect and have a narrow scope of application.

[0040] In view of this, the present invention provides a method for detecting extremely deep energy level traps, which can convert deeper energy level defects into shallower energy level defects by injecting electrons into the semiconductor to be tested, and then use the DLTS method to detect the injected semiconductor to be tested to obtain the trap concentration at the deeper energy level, thereby realizing the detection of the trap concentration at the deeper energy level and expanding the detection range; since the present invention does not adopt the deep energy level spectroscopy method, it can realize the detection of semiconductor devices that are insensitive to light excitation and non-transparent semiconductor devices, and there is no need to use lasers; therefore, the present invention has a wider scope of application.

[0041] The present invention is further described in detail below with reference to specific embodiments, but the embodiments of the present invention are not limited thereto.

[0042] Figure 1 The diagram shows a schematic diagram of the formation energy of a trap provided by an embodiment of the present invention changing with the energy level.

[0043] See also Figure 1 , Figure 1 The curve in the figure intuitively shows the relationship between the trap energy level and the charged state in the semiconductor material, that is, how the formation energy of traps with different charged states changes when the Fermi level of the material changes from the top of the valence band to the bottom of the conduction band. Figure 1 Several line segments with different slopes, such as A1A2, A2A3, and A3A4, correspond to different charged states.

[0044] The slope of each line segment is positively correlated with the charge state q of the trap, that is, the slope of the line segment varies with the charge state. The higher the charge state, the greater the slope. When the Fermi level reaches a certain value, the different charge states of the trap will switch, and these points are the charge state transition points. Figure 1 The inflection points in: point A1, point A2, point A3, point A4, correspond to the energy level positions of the traps.

[0045] For example, the nitrogen interstitial (N) in wide bandgap GaN materials i ) as an example, N i -1 state, the defect carries a negative charge and has an extra electron; N i 0 state, the defect has no charge; N i +1 state, the defect has a positive charge and lacks an electron; N i +2 state, the defect has two positive charges and lacks two electrons; N i +3 The defect has three positive charges and lacks three electrons. Gallium vacancies with different charge states have their own corresponding energy levels (i.e., charge state transition points), N i +3 Convert to N i +2 The transition point (energy level) is about E C -2.6eV; N i +2 Convert to N i +1 The transition point (energy level) is about E C -1.9eV; N i +1 Convert to N i 0 The transition point (energy level) is about E C -1.2eV; N i 0 Convert to N i -1 The transition point (energy level) is about E C -0.6eV.

[0046] Therefore, for defects at the charge state transition point, filling electrons in a defect at a deeper energy level can convert it to a defect at a shallower energy level. For example, filling an electron in a nitrogen interstitial defect at a charge state transition of (+3 / +2) can convert this defect into a nitrogen interstitial defect at a charge state transition of (+2 / +1).

[0047] Figure 2The flowchart shown is a method for detecting a very deep energy level trap provided by an embodiment of the present invention. The method can be applied to the following very deep energy level trap detection device 400. As an example but not a limitation, the method can include steps S301-S304, and each step is described below.

[0048] S301, based on deep level transient spectroscopy, detecting the concentration of the shallowest energy level traps of the original semiconductor to be tested.

[0049] In one example, the deep energy level transient spectrum of the original semiconductor to be tested can be obtained through the above steps S101-S104, and the spectral lines of the deep energy level transient spectrum of the original semiconductor to be tested under different rate windows can be analyzed to obtain the Allenius curve of the original semiconductor to be tested. The Allenius curve of the original semiconductor to be tested is identified to obtain the concentration of the shallowest energy level trap of the original semiconductor to be tested.

[0050] S302, performing an nth electron injection on the semiconductor to be tested according to the nth electron beam filling dose to fill at least one electron in each defect of the semiconductor to be tested after the (n-1)th injection, to obtain the semiconductor to be tested after the nth injection.

[0051] Exemplarily, n is a positive integer less than or equal to N-1, and N is the maximum number of energy levels of the same defect in the original semiconductor to be tested.

[0052] Exemplarily, the semiconductor to be tested after the 0th injection may be the original semiconductor to be tested.

[0053] In a possible implementation, the number x of electrons filled in each defect during the nth electron injection may be the difference in charge state between the (n+1)th shallow energy level trap and the nth shallow energy level trap of the original semiconductor to be tested.

[0054] For example, if the shallowest energy level trap of the original semiconductor to be tested is a (+1 / +0) charge state conversion defect, and the next shallowest is a (+3 / +2) charge state defect, then during the first electron injection, 2 electrons can be filled in each defect, so that the (+3 / +2) charge state defect is converted into a (+1 / +0) charge state conversion defect.

[0055] For example, if the shallowest energy level trap of the original semiconductor to be tested is a (+1 / +0) charge state conversion defect, and the next shallowest is a (+2 / +1) charge state defect, then during the first electron injection, one electron can be filled in each defect, so that the (+2 / +1) charge state defect is converted into a (+1 / +0) charge state conversion defect.

[0056] In one example, if the material of the original semiconductor to be tested is gallium nitride, there are four energy levels of nitrogen interstitial defects in this material (i.e., N=4), which are respectively: (0 / -1) charge state conversion nitrogen interstitial defect, (+1 / +0) charge state conversion nitrogen interstitial defect, (+2 / +1) charge state conversion nitrogen interstitial defect, (+3 / +2) charge state conversion nitrogen interstitial defect. Therefore, one electron can be filled in each defect each time electron injection is performed.

[0057] In a possible implementation, the nth electron beam filling dosage used in the nth filling may be determined according to the concentration of the (n+1)th shallow energy level trap of the original semiconductor to be tested.

[0058] Exemplarily, the nth electron beam filling dose may be approximately equal to the product of the concentration of the (n+1)th shallow energy level trap of the original semiconductor to be tested and x, so that x electrons can be filled in each defect during electron injection.

[0059] For example, if the shallowest energy level trap in the original semiconductor to be tested is a (0 / -1) charge state conversion defect, and the next shallowest is a (+2 / +1) charge state defect, then x=2, and the first electron beam filling dose can be 2p, where p is the concentration of the (+1 / 0) charge state defect in the original semiconductor to be tested.

[0060] In one example, generally, the concentration of each energy level defect in a semiconductor is about one thousandth of its doping concentration, and the nth electron beam filling dose may be about the product of one thousandth of the doping concentration of the original semiconductor to be tested and x.

[0061] S303, based on deep level transient spectroscopy, detecting the concentration of the shallowest energy level trap of the semiconductor to be tested after the nth injection, and obtaining the concentration of the (n+1)th shallowest energy level trap of the original semiconductor to be tested.

[0062] In one example, similarly, the deep energy level transient spectrum of the semiconductor to be tested after the n-th injection can be obtained through the above steps S101-S104, and the spectrum lines of the deep energy level transient spectrum of the semiconductor to be tested after the n-th injection (i.e., the n-th deep energy level transient spectrum) under different rate windows can be analyzed to obtain the Allenius curve of the semiconductor to be tested after the n-th injection (i.e., the n-th Allenius curve). The Allenius curve is identified to obtain the concentration of the shallowest energy level trap of the semiconductor to be tested after the n-th injection, and finally the concentration of the shallowest energy level trap of the semiconductor to be tested after the n-th injection is used as the concentration of the n+1-th shallow energy level trap of the original semiconductor to be tested.

[0063] For example, if the material of the original semiconductor to be tested is gallium nitride, the concentration of its shallowest energy level defects can be first detected to obtain the concentration of nitrogen interstitial defects with charge state conversion (+1 / +0) in the original semiconductor to be tested; then the first electron injection is performed, one electron is injected into each defect to obtain the semiconductor to be tested after the first electron injection, and the concentration of the shallowest energy level defects of the semiconductor to be tested after the first electron injection is detected to obtain the concentration of nitrogen interstitial defects with charge state conversion (+2 / +1). Electron injection is performed again on the semiconductor to be tested after the first electron injection, one electron is injected into each defect to obtain the semiconductor to be tested after the second electron injection, and the concentration of the shallowest energy level defects of the semiconductor after the second electron injection is detected to obtain the concentration of nitrogen interstitial defects with charge state conversion (+3 / +2) in the original semiconductor to be tested.

[0064] S304, determine whether n is equal to N-1.

[0065] In one example, if n=N-1, it means that all energy level traps of the original semiconductor to be tested have been detected, and the detection can be stopped.

[0066] In another example, if n is less than N-1, it means there are still undetected traps, and n=n+1 is set to execute steps S302-S304 to perform the next detection.

[0067] According to the method provided by the present invention, defects at deeper energy levels can be converted into defects at shallower energy levels by injecting electrons into the semiconductor to be tested, and then the DLTS method is used to detect the injected semiconductor to obtain the trap concentration at deeper energy levels, thereby realizing the detection of the trap concentration at deeper energy levels and expanding the detection range. Since the present invention does not adopt the deep energy level spectroscopy method, it can realize the detection of semiconductor devices that are insensitive to light excitation and non-transparent semiconductor devices, and there is no need to use lasers. Therefore, the present invention has a wider scope of application.

[0068] Figure 3 The structure diagram of a detection device for extremely deep energy level traps provided by an embodiment of the present invention is shown. As an example but not a limitation, the device 400 may include a deep energy level transient spectrum detection module 410 and an electron injection module 420 .

[0069] Exemplarily, the deep energy level transient spectrum detection module 410 is used to detect the concentration of the shallowest energy level traps of the original semiconductor to be tested based on the deep energy level transient spectrum method; the electron injection module 420 is used to perform the nth electron injection on the semiconductor to be tested according to the nth electron beam filling dose to fill at least one electron in each defect of the semiconductor to be tested after the n-1th injection, and obtain the semiconductor to be tested after the nth injection, wherein the semiconductor to be tested after the 0th injection is the original semiconductor to be tested, n is a positive integer less than or equal to N-1, and N is the maximum number of energy levels of the same defect in the original semiconductor to be tested; the deep energy level transient spectrum detection module 410 is also used to detect the concentration of the shallowest energy level traps of the semiconductor to be tested after the nth injection based on the deep energy level transient spectrum method, and obtain the concentration of the n+1th shallow energy level traps of the original semiconductor to be tested; wherein, after electron injection into the deeper energy level traps, the deeper energy level traps can be converted into shallower energy level traps.

[0070] In one example, the deep energy level transient spectrum detection module 410 is specifically used to: acquire and obtain the nth deep energy level transient spectrum, wherein the nth deep energy level transient spectrum is the deep energy level transient spectrum of the semiconductor to be tested after the nth injection, analyze the spectral lines of the nth deep energy level transient spectrum under different rate windows, and obtain the nth Allenius curve; identify the nth Allenius curve to obtain the concentration of the shallowest energy level traps of the semiconductor to be tested after the nth injection, and use the concentration of the shallowest energy level traps of the semiconductor to be tested after the nth injection as the concentration of the n+1th shallow energy level traps of the original semiconductor to be tested.

[0071] In one example, the number of electrons filled in each defect during the n-th electron injection is the difference in charge state between the (n+1)th shallow energy level trap and the nth shallow energy level trap of the original semiconductor to be tested.

[0072] In one example, the material of the original semiconductor to be tested includes gallium nitride, the type of defect is nitrogen interstitial defect, N is equal to 4, and the nitrogen interstitial defects in the original semiconductor to be tested are, from shallow to deep: (0 / -1) nitrogen interstitial defect with charge state conversion, (+1 / +0) nitrogen interstitial defect with charge state conversion, (+2 / +1) nitrogen interstitial defect with charge state conversion, and (+3 / +2) nitrogen interstitial defect with charge state conversion. Each time electron injection is performed, the number of electrons filled in each defect is 1.

[0073] In one example, the nth electron beam filling dose is determined according to the concentration of the n+1th shallow energy level trap of the original semiconductor to be tested.

[0074] According to the device provided by the present invention, by injecting electrons into the semiconductor to be tested, defects at deeper energy levels can be converted into defects at shallower energy levels, and then the DLTS method is used to detect the injected semiconductor to be tested to obtain the trap concentration at deeper energy levels, thereby realizing the detection of the trap concentration at deeper energy levels and expanding the detection range. Since the present invention does not adopt the deep energy level spectroscopy method, it can realize the detection of semiconductor devices that are insensitive to light excitation and non-transparent semiconductor devices, and there is no need to use lasers. Therefore, the scope of application of the present invention is relatively wide.

[0075] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0076] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0077] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art may understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit may implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0078] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, any modifications made without departing from the concept of the present invention should be deemed to belong to the protection scope of the present invention.

Claims

1. A method for detecting a very deep energy level trap, characterized in that: include: Based on deep level transient spectroscopy, the concentration of the shallowest energy level traps in the original semiconductor to be tested is detected; According to the nth electron beam filling dose, the semiconductor to be tested is subjected to an nth electron injection to fill at least one electron in each defect of the semiconductor to be tested after the n-1th injection, to obtain the semiconductor to be tested after the nth injection, wherein the semiconductor to be tested after the 0th injection is the original semiconductor to be tested, n is a positive integer less than or equal to N-1, and N is the maximum number of energy levels of the same defect in the original semiconductor to be tested; Based on deep level transient spectroscopy, the concentration of the shallowest energy level trap of the semiconductor to be tested after the n-th injection is detected to obtain the concentration of the (n+1)th shallow energy level trap of the original semiconductor to be tested; Among them, after electron injection into the deeper energy level trap, the deeper energy level trap can be converted into a shallower energy level trap.

2. The method according to claim 1, characterized in that: The method of detecting the concentration of the shallowest energy level trap of the semiconductor to be tested after the n-th injection based on the deep energy level transient spectroscopy method to obtain the concentration of the (n+1)th shallow energy level trap of the original semiconductor to be tested comprises: Acquire and obtain the nth deep energy level transient spectrum, wherein the nth deep energy level transient spectrum is the deep energy level transient spectrum of the semiconductor to be tested after the nth injection, Analyze the spectral lines of the n-th deep energy level transient spectrum under different rate windows to obtain the n-th Allenius curve; The nth Allenius curve is identified to obtain the concentration of the shallowest energy level traps of the semiconductor to be tested after the nth injection, and the concentration of the shallowest energy level traps of the semiconductor to be tested after the nth injection is used as the concentration of the (n+1)th shallowest energy level traps of the original semiconductor to be tested.

3. The method according to claim 1, characterized in that The number of electrons filled in each defect during the n-th electron injection is the difference in charge state between the (n+1)th shallow energy level trap and the (n)th shallow energy level trap of the original semiconductor to be tested.

4. The method according to claim 3, characterized in that: The material of the original semiconductor to be tested includes gallium nitride, the type of defect is nitrogen interstitial defect, N is equal to 4, and the nitrogen interstitial defects in the original semiconductor to be tested are, from shallow to deep: (0 / -1) nitrogen interstitial defect with charge state conversion, (+1 / +0) nitrogen interstitial defect with charge state conversion, (+2 / +1) nitrogen interstitial defect with charge state conversion, and (+3 / +2) nitrogen interstitial defect with charge state conversion. Each time electron injection is performed, the number of electrons filled in each defect is 1.

5. The method according to claim 1, characterized in that The nth electron beam filling dose is determined according to the concentration of the n+1th shallow energy level trap of the original semiconductor to be tested.

6. A detection device for extremely deep energy level traps, characterized in that: include: A deep level transient spectrum detection module, which is used to detect the concentration of the shallowest energy level traps of the original semiconductor to be tested based on the deep level transient spectrum method; An electron injection module, the electron injection module is used to perform an nth electron injection on the semiconductor to be tested according to an nth electron beam filling dose to fill at least one electron in each defect of the semiconductor to be tested after the n-1th injection, to obtain the semiconductor to be tested after the nth injection, wherein the semiconductor to be tested after the 0th injection is the original semiconductor to be tested, n is a positive integer less than or equal to N-1, and N is the maximum number of energy levels of the same defect in the original semiconductor to be tested; The deep energy level transient spectrum detection module is also used to detect the concentration of the shallowest energy level trap of the semiconductor to be tested after the nth injection based on the deep energy level transient spectrum method, and obtain the concentration of the (n+1)th shallow energy level trap of the original semiconductor to be tested; Among them, after electron injection into the deeper energy level trap, the deeper energy level trap can be converted into a shallower energy level trap.

7. The device according to claim 6, characterized in that The deep level transient spectrum detection module is also used for: Acquire and obtain the nth deep energy level transient spectrum, wherein the nth deep energy level transient spectrum is the deep energy level transient spectrum of the semiconductor to be tested after the nth injection, Analyze the spectral lines of the n-th deep energy level transient spectrum under different rate windows to obtain the n-th Allenius curve; The nth Allenius curve is identified to obtain the concentration of the shallowest energy level traps of the semiconductor to be tested after the nth injection, and the concentration of the shallowest energy level traps of the semiconductor to be tested after the nth injection is used as the concentration of the (n+1)th shallowest energy level traps of the original semiconductor to be tested.

8. The device according to claim 6, characterized in that The number of electrons filled in each defect during the n-th electron injection is the difference in charge state between the (n+1)th shallow energy level trap and the (n)th shallow energy level trap of the original semiconductor to be tested.

9. The device according to claim 8, characterized in that The material of the original semiconductor to be tested includes gallium nitride, the type of defect is nitrogen interstitial defect, N is equal to 4, and the nitrogen interstitial defects in the original semiconductor to be tested are, from shallow to deep: (0 / -1) nitrogen interstitial defect with charge state conversion, (+1 / +0) nitrogen interstitial defect with charge state conversion, (+2 / +1) nitrogen interstitial defect with charge state conversion, and (+3 / +2) nitrogen interstitial defect with charge state conversion. Each time electron injection is performed, the number of electrons filled in each defect is 1.

10. The device according to claim 6, characterized in that The nth electron beam filling dose is determined according to the concentration of the n+1th shallow energy level trap of the original semiconductor to be tested.

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