CN107169160B - A Calculation Method for Non-Ionization Energy Loss of Heterojunction Bipolar Transistors - Google Patents

Abstract

The invention discloses a method for calculating non-ionization energy loss of a heterojunction bipolar transistor, which relates to the technical field of environmental engineering, utilizes SRIM software to simulate the process of space radiation particles entering an InP/InGaAs HBT device, accurately calculates the relation between the non-ionization energy loss and the energy of the incident particles in the device to predict the performance degradation condition of the device in the space radiation environment, can determine a characteristic curve only by few tests, and saves the test expenditure and cost.

Description

A Calculation Method for Non-Ionization Energy Loss of Heterojunction Bipolar Transistors

technical field

The invention relates to the technical field of environmental engineering, in particular to a method for calculating the non-ionization energy loss of a heterojunction bipolar transistor.

Background technique

Indium phosphide heterojunction bipolar transistor InP HBT has the advantages of ultra-high frequency characteristics, large power density and good linearity. In the communication system, the RF front-end circuit plays a role in the mutual conversion of wireless signals and digital signals, thus forming a transceiver system, including low-noise amplifiers, power amplifiers, voltage-controlled oscillators, mixers and other circuits. In terms of implementation, InP-based devices and circuits have advantages that other devices do not have. Therefore, InP-based devices and circuits will be widely used in military fields such as satellites and radars in the future.

InP devices and circuits, which are widely used in the aerospace field, will be bombarded by high-energy protons, neutrons, alpha particles, heavy ions and other particles in a severe space radiation environment, resulting in various radiation effects, such as total dose effect, displacement Effects and single event effects, these radiation effects cause instantaneous or permanent changes in device or circuit performance, and then make the entire spacecraft electrical system functional failure. Therefore, before the device is damaged, we need to have a certain ability to predict the device characteristics.

Non-ionizing energy loss (NIEL) describes the displacement damage of the device after space radiation particles are incident on the device. The research on NIEL can give people a deeper understanding of the radiation damage process, and can also use it to predict the performance of devices or circuits in the radiation environment, so it is more widely used.

However, only considering the contribution of displacement damage to NIEL has limitations. Through research, it is found that the non-ionization energy loss NIEL not only causes the displacement of atoms, but also generates a large number of phonons, that is, lattice vibrations, which promote the displacement of atoms and increase the NIEL. We know that there is a linear relationship between the device damage factor and NIEL, and the device performance can be predicted by the NIEL value. Therefore, solving for an accurate NIEL value is crucial.

SUMMARY OF THE INVENTION

The embodiment of the present invention provides a method for calculating the non-ionization energy loss of a heterojunction bipolar transistor, which can solve the problems existing in the prior art.

A method for calculating non-ionization energy loss of a heterojunction bipolar transistor, the method comprising the following steps:

The SRIM software was used to simulate the process of particles entering the InP/InGaAs HBT device in the space radiation environment, and the relationship between the non-ionization energy loss in the device and the energy of the incident particles was calculated using the simulation results;

The non-ionization energy loss includes the energy consumed to generate vacancies and the energy consumed to generate phonons. The energy M ₁ required to generate a vacancy is shown in formula (1):

In formula (1), T _d refers to the atomic displacement threshold energy in the irradiated device;

The energy M ₂ required to generate a phonon is shown in formula (2):

In formula (2), h is Planck's constant, c is the speed of light, λ is the length of the Raman spectrum, and A is the coefficient;

Use the simulation results to calculate the relationship between the non-ionization energy loss NIEL and the incident depth D, see formula (3):

In formula (3), IONV(D) and RECV(D) refer to the number of vacancies generated within a unit distance of an incident atom and a recoil atom, respectively, IONP(D) and RECP(D) refer to an incident atom and The number of phonons generated within a unit distance of a recoil atom, ρ is the atomic density of the material;

To solve the relationship between the incident particle energy E and the incident depth D, see formulas (4)-(7):

F(D)=10000{M ₁ [IONV(D)+RECV(D)]+M ₂ [IONP(D)+RECP(D)]}+10[IONI(D)+RECI(D)]

(4)

In formula (4), F(D) refers to the energy required to generate vacancies, phonons and atomic ionization per unit length, IONI(D) and RECI(D) represent an incident atom and a recoil atom per unit distance, respectively. ionization energy loss within;

E _c (D)=B×F(D) (5)

In formula (5), E _c (D) refers to the accumulated atomic energy consumed in the length interval B;

In formula (6), E _t (D) refers to the total energy that needs to be consumed when the incident particle reaches a certain depth;

E(D)=E ₀ -E _t (D) (7)

In formula (7), E ₀ is the initial energy of the incident particle, and E(D) refers to the energy of the particle on the incident path;

Combining the relationship curve between the non-ionization energy loss NIEL and the incident depth D obtained in equation (3), and the change relationship curve between the incident particle energy E and the incident depth D obtained in equation (7), the non-ionization energy loss NIEL is finally obtained. Relationship curve with incident particle energy E.

The invention uses SRIM software to simulate the process of space radiation particles incident on an InP/InGaAs HBT device, accurately calculates the relationship between the loss of non-ionization energy in the device and the energy of the incident particles, and predicts the performance degradation of the device in the space radiation environment. The characteristic curve can be determined by the test, which saves the cost and cost of the test.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

Figure 1 shows the SRIM simulation results: (a) the relationship between the ionization, phonon and vacancy generation rates introduced by incident protons and the incidence depth D, (b) the ionization, phonon and vacancy generation rates introduced by recoil atoms and the incidence depth D the relationship diagram;

Fig. 2 is the relationship diagram of non-ionization energy loss NIEL and incident depth D;

Fig. 3 is the relationship diagram of the cumulative energy consumption E _c and the incident depth D in the unit interval;

Fig. 4 is the relationship diagram of the total accumulated energy consumption E _t and the incident depth D;

Fig. 5 is the relation diagram of incident proton energy E and incident depth D;

Fig. 6 is the relationship diagram of non-ionization energy loss NIEL and incident proton energy E;

Fig. 7 is the relation diagram of NIEL and incident proton energy E considering and not considering the influence of phonon;

Figure 8 is a graph comparing the relationship between the NIEL of different particles incident and the incident particle energy E.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

A method for calculating the non-ionization energy loss of a heterojunction bipolar transistor provided in the embodiment of the present invention includes the following steps:

In the first step, the SRIM software is used to simulate the process of particles entering the InP/InGaAs HBT device in the space radiation environment, and the relationship between the non-ionization energy loss in the device and the energy of the incident particles is calculated by using the simulation results;

In the second step, the non-ionization energy loss mainly includes the energy consumed to generate vacancies and the energy consumed to generate phonons. The energy M ₁ required to generate a vacancy is shown in formula (1):

In formula (1), the unit of M ₁ is keV/vacancy, and T _d refers to the atomic displacement threshold energy in the irradiated device, and the unit is eV;

The energy M ₂ required to generate a phonon is shown in formula (2):

In formula (2), the unit of M ₂ is keV/phonon, h is Planck's constant, c is the speed of light, λ is the length of the Raman spectrum, and A is the coefficient;

The third step is to use the simulation results to calculate the relationship between the non-ionization energy loss NIEL and the incident depth D, see formula (3):

In formula (3), the unit of NIEL is MeV·cm ² /g, IONV(D) and RECV(D) refer to the number of vacancies generated within a unit distance of an incident atom and a recoil atom, respectively, IONP(D) and RECP(D) refers to the number of phonons generated within a unit distance of an incident atom and a recoil atom respectively, and the above are all SRIM simulation results; ρ is the atomic density of the material;

The fourth step is to solve the relationship curve of the incident particle energy E with the incident depth D, see formulas (4)-(7):

F(D)=10000{M ₁ [IONV(D)+RECV(D)]+M ₂ [IONP(D)+RECP(D)]}+10[IONI(D)+RECI(D)]

(4)

In formula (4), F(D) refers to the energy required to generate vacancies, phonons and atomic ionization per unit length, in keV/μm, IONI(D) and RECI(D) represent an incident atom and The ionization energy loss per unit distance of a recoil atom;

E _c (D)=B×F(D) (5)

In formula (5), E _c (D) refers to the atomic energy consumed cumulatively over the length interval B, where the unit of B is μm;

In formula (6), E _t (D) refers to the total energy that needs to be consumed when the incident particle reaches a certain depth;

E(D)=E ₀ -E _t (D) (7)

In formula (7), E ₀ is the initial energy of the incident particle, and E(D) refers to the energy of the particle on the incident path;

In the fifth step, combining the relationship curve between the non-ionization energy loss NIEL and the incident depth D obtained in formula (3), and the change relationship curve between the incident particle energy E and the incidence depth D obtained in formula (7), we can finally get Non-ionization energy loss NIEL versus incident particle energy E. The damage factor of the device is linearly related to NIEL, therefore, the performance of the device can be predicted by solving the NIEL.

The present invention will be further described below in conjunction with a specific example.

1. Take protons as an example, set the initial energy E ₀ =10MeV, use SRIM software to simulate the process of protons entering the device in the space radiation environment of InP/InGaAs HBT devices, and obtain the ionization, phonon and vacancy generation rates introduced by incident protons and incident depth as a function of depth, as shown in Fig. 1(a), and ionization, phonon and vacancy generation rates introduced by recoil atoms as a function of incident depth, as shown in Fig. 1(b);

2. Calculate the relationship between the non-ionization energy loss and the incident depth in the device based on the simulation results;

1) First, the energy required to generate a vacancy and the energy required to generate a phonon can be obtained from formula (1) and formula (2);

2) Combining the simulation results and formula (3), the relationship between the non-ionization energy loss in the device and the incident depth can be obtained, as shown in Figure 2. It was found that the deeper the depth of incidence, the greater the value of non-ionizing energy loss. That is to say, the position where the particle incidence stops will be the most damaged area.

3. Solve the relationship curve between the incident particle energy E and the incident depth D;

1) Calculate the energy F(D) required to generate vacancies, phonons and atomic ionization per unit length, in keV/μm, see formula (4);

2) Knowing F(D), find the atomic energy E _c (D) that is consumed cumulatively over the length interval B, the unit of B is μm, see formula (5), as shown in Figure 3;

3) When the incident proton reaches a certain depth, the total energy E _t (D) that needs to be consumed, see formula (6), as shown in Figure 4;

4) When the incident proton reaches a certain depth, the energy E(D), see formula (7), as shown in Figure 5, it is found that with the continuous increase of the incident depth, the proton energy gradually decreases until it is zero, Finally stop inside the device;

4. Combining the relationship between the non-ionization energy loss NIEL and the incident depth D obtained earlier, and the relationship between the incident particle energy E and the incident depth D, the relationship between the non-ionization energy loss NIEL and the incident proton energy E can finally be obtained, such as As shown in Figure 6, it is found that the lower the proton energy, the greater the damage to the device, mainly due to the low energy protons entering the device, the speed is slow, the interaction time with the device is longer, the effect area is large, and the deposition more energy and, therefore, greater damage. At the same time, the results of calculating NIEL by the analytical method are given. It can be seen from the comparison that the calculation method of NIEL that uses SRIM software to simulate and consider phonon interaction described in this patent is correct. The damage coefficient of the device has a linear relationship with NIEL, so the performance of the device can be predicted by solving the NIEL;

5. Based on the above method, compare the relationship between NIEL and incident proton energy with and without phonon interaction, as shown in Figure 7. It was found that the NIEL values considering phonons all increased, indicating that phonons promote the displacement of atoms and increase the damage value of non-ionization energy;

6. The above method is applicable to other space radiation particles, such as carbon, helium and other particles. As shown in Figure 8, it is found that the greater the atomic mass, the greater the non-ionization energy loss NIEL. The main reason is that the greater the atomic mass, the greater the collision with the target atoms, the deposition of more energy, and the greater the damage.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flows of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

Although preferred embodiments of the present invention have been described, additional changes and modifications to these embodiments may occur to those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be construed to include the preferred embodiment and all changes and modifications that fall within the scope of the present invention.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (1)

1. a calculation method of non-ionization energy loss of heterojunction bipolar transistor, is characterized in that, this method comprises the following steps: The SRIM software was used to simulate the process of particles entering the InP/InGaAs HBT device in the space radiation environment, and the relationship between the non-ionization energy loss in the device and the energy of the incident particles was calculated using the simulation results; The non-ionization energy loss includes the energy consumed to generate vacancies and the energy consumed to generate phonons. The energy M ₁ required to generate a vacancy is shown in formula (1):

In formula (1), T _d refers to the atomic displacement threshold energy in the irradiated device; The energy M ₂ required to generate a phonon is shown in formula (2):

In formula (2), h is Planck's constant, c is the speed of light, λ is the length of the Raman spectrum, and A is the coefficient; Use the simulation results to calculate the relationship between the non-ionization energy loss NIEL and the incident depth D, see formula (3):

In formula (3), IONV(D) and RECV(D) refer to the number of vacancies generated within a unit distance of an incident atom and a recoil atom, respectively, IONP(D) and RECP(D) refer to an incident atom and The number of phonons generated within a unit distance of a recoil atom, ρ is the atomic density of the material; To solve the relationship between the incident particle energy E and the incident depth D, see formulas (4)-(7): F(D)=10000{M ₁ [IONV(D)+RECV(D)]+M ₂ [IONP(D)+RECP(D)]}+10[IONI(D)+RECI(D)] (4) In formula (4), F(D) refers to the energy required to generate vacancies, phonons and atomic ionization per unit length, IONI(D) and RECI(D) represent an incident atom and a recoil atom per unit distance, respectively. ionization energy loss within; E _c (D)=B×F(D) (5) In formula (5), E _c (D) refers to the accumulated atomic energy consumed in the length interval B;

In formula (6), E _t (D) refers to the total energy that needs to be consumed when the incident particle reaches a certain depth; E(D)=E ₀ -E _t (D) (7) In formula (7), E ₀ is the initial energy of the incident particle, and E(D) refers to the energy of the particle on the incident path; Combining the relationship curve between the non-ionization energy loss NIEL and the incident depth D obtained in equation (3), and the change relationship curve between the incident particle energy E and the incident depth D obtained in equation (7), the non-ionization energy loss NIEL is finally obtained. Relationship curve with incident particle energy E.

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