CN106299014A - The parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode and platform - Google Patents

Abstract

The invention discloses parameter optimization method and the platform of a kind of near-infrared single photon avalanche optoelectronic diode, correlation technique includes: obtain the structural parameters at a temperature of predetermined work of the near-infrared single photon avalanche optoelectronic diode of input；According to structural parameters and combine Gauss equation and calculate the Electric Field Distribution of near-infrared single photon avalanche optoelectronic diode, and then obtain the avalanche probability of near-infrared single photon avalanche optoelectronic diode dynode layer each position；The intrinsic parameters of near-infrared single photon avalanche optoelectronic diode is calculated according to the avalanche probability obtained and Electric Field Distribution.The program is suitable for the III V material system of all employing separate absorbent graded charge multiplication (SAGCM) heterojunction structure, it is achieved that single-photon avalanche photoelectric diode structure parameter and the global optimization of working condition.

Description

The parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode and platform

Technical field

The present invention relates to quantum information technology field, particularly relate to the ginseng of a kind of near-infrared single photon avalanche optoelectronic diode Number optimization method and platform.

Background technology

Single-photon detector is the faint light detection instrument that sensitivity is the highest, in many field such as quantum communications, photon Radar, laser imaging, fluorescence detection etc. have extensive and important application.

At near infrared band, single photon detection kind currently mainly includes photomultiplier tube, single-photon avalanche photoelectricity two Pole pipe, superconducting nano-wire single-photon detector, frequency upooaversion detector etc..Various detectors have its corresponding pluses and minuses, Such as, the detection efficient of photomultiplier tube is low, noise is high, superconducting nano-wire single-photon detector detection efficient, dark counting, time Between all possess advantage in several performance indications such as resolution, but need that the working environment of super low temperature refrigeration, cost are high, volume is big.And Single-photon avalanche photodiode because of its need not super low temperature refrigeration, low cost, volume is little, be prone to the system integration, stable performance A series of advantages such as reliable, have been widely used in the most practical quantum communications field.

In order to realize the detection of near-infrared single photon, single-photon avalanche photoelectric diode (Single-Photon Avalanche Diode, hereinafter referred to as SPAD) need to be operated in Geiger mode angular position digitizer.The reverse-biased electricity at SPAD two ends in such a mode Pressure is more than its avalanche voltage, and the electric field intensity in the PN junction of SPAD reaches 1E5V/cm magnitude.When single photon incides this PN Can produce pair of electrons hole pair in Jie, electron hole pair accelerates two polar motions toward SPAD under the effect of highfield, at this Can collide with lattice during individual and ionize and produce increasing electron hole pair, thus form avalanche effect, work as snow Collapse after electric current exceedes the threshold value of reading circuit and be i.e. detected.

Currently, the avalanche diode near infrared band single photon detection generally uses separate absorbent gradual change electricity The III-V material system of lotus multiplication (SAGCM) heterojunction structure includes InGaAs/InP, InGaAs/InAlAs etc..But, The avalanche diode device used in a lot of reality is originally used for Conventional optical communication, does not enters single photon detection when device designs Row optimization causes single photon detection poor performance and concordance poor.

Summary of the invention

It is an object of the invention to provide parameter optimization method and the platform of a kind of near-infrared single photon avalanche optoelectronic diode, It is suitable for the III-V material system of all employing separate absorbent graded charge multiplication (SAGCM) heterojunction structure, it is achieved Single-photon avalanche photoelectric diode structure parameter and the global optimization of working condition.

It is an object of the invention to be achieved through the following technical solutions:

A kind of parameter optimization method of near-infrared single photon avalanche optoelectronic diode, including:

Obtain the structural parameters at a temperature of predetermined work of the near-infrared single photon avalanche optoelectronic diode of input；

According to structural parameters and combine Gauss equation calculate near-infrared single photon avalanche optoelectronic diode Electric Field Distribution, enter And obtain the avalanche probability of near-infrared single photon avalanche optoelectronic diode dynode layer each position；

The intrinsic parameters of near-infrared single photon avalanche optoelectronic diode is calculated according to the avalanche probability obtained and Electric Field Distribution.

Described according to structural parameters and combine Gauss equation calculate near-infrared single photon avalanche optoelectronic diode electric field divide The expression formula of cloth is:

$\▿\·E=\frac{\mathrm{\ρ}}{{\mathrm{\ϵ}}_i};$

Above formula becomes under one-dimensional condition:

$E\left(x\right)=E_i-\frac{qd}{{\mathrm{\ϵ}}_i}x;$

Wherein, for divergence, E is electric field intensity, and ρ is charge density, ε_iFor near-infrared single photon avalanche optoelectronic diode The dielectric constant of the i-th layer material, E_iThe maximum field intensity calculated for aforementioned Gauss equation, q is elementary charge unit, E (x) For the electric field intensity at the x of position, d is the thickness of x place, position layer.

The formula of the avalanche probability calculating near-infrared single photon avalanche optoelectronic diode dynode layer each position includes:

$\frac{{\mathrm{dP}}_e}{dx}=(1-P_e){\mathrm{\α}}_e\[P_e+P_h-P_e\·P_h\];$

$\frac{{\mathrm{dP}}_h}{dx}=-(1-P_h){\mathrm{\α}}_h\[P_e+P_h-P_e\·P_h\];$

In above formula, P_eWith P_hIt is respectively electronics and x' position in near-infrared single photon avalanche optoelectronic diode dynode layer, hole Put the probability of triggering avalanche, α_eWith α_hIt is respectively electronics and hole x' in near-infrared single photon avalanche optoelectronic diode dynode layer The ionization coefficient of position；

Then electronics and hole are to the probability of x position triggering avalanche in near-infrared single photon avalanche optoelectronic diode dynode layer P_b(x') it is:

P_b(x')=1-(1-p_e(x'))(1-p_h(x'))；

Above-mentioned ionization coefficient α_eWith α_hCalculate according to electric field intensity:

${\mathrm{\α}}_h(F,T)=\frac{F}{E_{th\_h}}\exp (-\frac{E_{th\_h}}{\frac{{\left({\mathrm{F\λ}}_h\right)}^2}{3E_{P_h}}+{\mathrm{F\λ}}_h+kT});$

${\mathrm{\α}}_e(F,T)=\frac{F}{E_{th\_e}}\exp (-\frac{E_{th\_e}}{\frac{{\left({\mathrm{F\λ}}_e\right)}^2}{3E_{P_e}}+{\mathrm{F\λ}}_e+kT})(c_{e}T+d_e);$

Wherein, F is the electric field intensity of near-infrared single photon avalanche optoelectronic diode dynode layer, and k is that Boltzmann is normal Number, T is predetermined work temperature；E_{th_h}=1.45eV, E_{th_e}=1.60eV,

The intrinsic parameters of described near-infrared single photon avalanche optoelectronic diode includes: avalanche voltage, detection efficient and secret mark Number.

Described avalanche voltage is P_e(0)=0 or P_h(W) voltage when=0；Wherein, W is near-infrared single photon avalanche optoelectronic The gross thickness of all layers of diode.

Described detection efficient P_dComputing formula be:

P_d=P_a·P_c·P_b；

Wherein, P_aFor the absorbing probability of photon, it is expressed as: P_a=(1-R) (1-exp (-α_absD')), in formula, R is monochromatic light The son reflection coefficient on near-infrared single photon avalanche optoelectronic diode surface, α_absFor near-infrared single photon avalanche optoelectronic diode The absorbed layer absorptance to single photon, d' is the thickness of absorbed layer；P_c=1；P_bProbability for avalanche layer triggering avalanche.

The computing formula of described secret mark number DCR is:

DCR=DCR_therm+DCR_tun-dir+DCR_tun-trap；

Wherein:

DCR_thermThe dark counting produced for thermal excitation, computing formula is:

${\mathrm{DCR}}_{therm}=\frac{n_i}{\mathrm{\τ}};$

In formula, n_iFor the carrier density in unit volume, τ is the life-span of carrier；

DCR_tun-dirThe dark counting produced for direct tunnelling, computing formula is:

${\mathrm{DCR}}_{tun-dir}={\mathrm{AE}}^2\exp \left(\frac{-{\mathrm{BE}}_g^{3/2}}{E}\right);$

In formula, E is electric field intensity,m_r=2 (m_cm_lh)/(m_c+m_lh), q is elementary charge unit, E_gCan carry for material, m_cFor the quality of conduction band electron, m_lhFor light hole Quality；

DCR_tun-trapThe dark counting caused for indirect tunnelling, computing formula is:

${\mathrm{DCR}}_{tun-trap}=\frac{{\mathrm{AE}}^2{N}_T\exp \left(\frac{-B_1{E}_{B1}^{3/2}+B_2{E}_{B2}^{3/2}}{E}\right)}{N_V\exp \exp \left(\frac{-B_1{E}_{B1}^{3/2}}{E}\right)+N_C\exp \exp \left(\frac{-B_2{E}_{B2}^{3/2}}{E}\right)}$

In formula,E_B1、E_B2It is respectively valence band and defect state Energy level difference, the energy level difference of conduction band and defect state, N_cAnd N_vRepresent conduction band and the density of states of valence band respectively.

The parameter optimization platform of a kind of near-infrared single photon avalanche optoelectronic diode, it is characterised in that this platform is for real Existing aforesaid method, this platform includes:

Structural parameters acquisition module, for obtain input near-infrared single photon avalanche optoelectronic diode at predetermined work At a temperature of structural parameters；

Electric Field Distribution and avalanche probability computing module, be used for according to structural parameters and combine Gauss equation calculating near-infrared list The Electric Field Distribution of photon avalanches photoelectric diode, and then obtain near-infrared single photon avalanche optoelectronic diode dynode layer each position Avalanche probability；

Intrinsic parameters computing module, for calculating near-infrared single photon snowslide according to the avalanche probability obtained with Electric Field Distribution The intrinsic parameters of photoelectric diode.

As seen from the above technical solution provided by the invention, by the physical analysis of single photon detection process with build Mould, can be with the avalanche voltage of calculating device, avalanche voltage with the change of device architecture, avalanche voltage variation with temperature, detection The parameters such as efficiency and dark counting, and these parameters are carried out OVERALL OPTIMIZA-TION DESIGN FOR and performance balance.

Accompanying drawing explanation

In order to be illustrated more clearly that the technical scheme of the embodiment of the present invention, required use in embodiment being described below Accompanying drawing be briefly described, it should be apparent that, below describe in accompanying drawing be only some embodiments of the present invention, for this From the point of view of the those of ordinary skill in field, on the premise of not paying creative work, it is also possible to obtain other according to these accompanying drawings Accompanying drawing.

The parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode that Fig. 1 provides for the embodiment of the present invention Flow chart；

The structural representation of the InGaAs/InP SPAD device that Fig. 2 provides for the embodiment of the present invention；

The parameter optimisation procedure schematic diagram that Fig. 3 provides for the embodiment of the present invention；

Electronics that Fig. 4 provides for the embodiment of the present invention and hole are at the avalanche probability distribution schematic diagram of dynode layer；

The avalanche voltage that Fig. 5 provides for the embodiment of the present invention is with the change curve schematic diagram of dynode layer thickness；

The avalanche voltage variation with temperature curve synoptic diagram that Fig. 6 provides for the embodiment of the present invention；

The detection efficient that Fig. 7 provides for the embodiment of the present invention is with the change curve schematic diagram of overvoltage；

The dark counting that Fig. 8 provides for the embodiment of the present invention is with the change curve schematic diagram of overvoltage；

Fig. 9 shows for the parameter optimization platform of a kind of near-infrared single photon avalanche optoelectronic diode that the embodiment of the present invention provides It is intended to.

Detailed description of the invention

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete Ground describes, it is clear that described embodiment is only a part of embodiment of the present invention rather than whole embodiments.Based on this Inventive embodiment, the every other enforcement that those of ordinary skill in the art are obtained under not making creative work premise Example, broadly falls into protection scope of the present invention.

The embodiment of the present invention provides the parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode, such as Fig. 1 institute Showing, it mainly comprises the steps:

Step 11, the structure at a temperature of predetermined work of the near-infrared single photon avalanche optoelectronic diode obtaining input are joined Number.

Step 12, according to structural parameters and combine Gauss equation calculate near-infrared single photon avalanche optoelectronic diode electric field Distribution, and then obtain the avalanche probability of near-infrared single photon avalanche optoelectronic diode dynode layer each position.

The avalanche probability that step 13, basis obtain and Electric Field Distribution calculate the basis of near-infrared single photon avalanche optoelectronic diode Levy parameter.

The such scheme of the embodiment of the present invention, is suitable for the multiplication of all employing separate absorbent graded charge (SAGCM) the III-V material system of heterojunction structure, such as InGaAs/InP, InGaAs/InAlAs etc..

Exemplary, the structural representation of InGaAs/InP SPAD device refers to Fig. 2, and it specifically includes that InP substrate Layer, InGaAs absorbed layer, InGaAsP transition zone, InP charge layer, InP dynode layer.InGaAs absorbed layer is used for absorbing near-infrared Single photon.InGaAsP transition zone is inserted in for reducing the discontinuity of energy inter-stage in the middle of InP charge layer and InGaAs layer, Thus reduce the carrier capture in interface.InP charge layer is for smoothing the low electric field in InGaAs absorbed layer and InP multiplication High electric field in Ceng, thus reduce the dark counting produced in InGaAs layer.

For the ease of understanding the present invention, 3 pairs of parameter optimisation procedure elaborate below in conjunction with the accompanying drawings.

As it is shown on figure 3, parameter optimisation procedure specifically includes that the structural parameters obtaining input, calculate Electric Field Distribution, calculate snow Collapse probability, calculate intrinsic parameters, including: avalanche voltage, detection efficient, dark counting etc..Specific as follows:

1, the structural parameters of input are obtained.

In the embodiment of the present invention, the structural parameters of input are the structural parameters at a temperature of predetermined work, specifically include that SPAD The material behavior of each layer, thickness, doping content, reversed bias voltage and other parameters.

2, Electric Field Distribution is calculated.

In the embodiment of the present invention, calculating SPAD each layer Electric Field Distribution by solving following Gauss equation, formula is as follows:

$\▿\·E=\frac{\mathrm{\ρ}}{{\mathrm{\ϵ}}_i};$

Wherein, for divergence, E is electric field intensity, and ρ is charge density, ε_iFor near-infrared single photon avalanche optoelectronic diode The dielectric constant of the i-th layer material.

Above formula can be changed under one-dimensional condition:

$E\left(x\right)=E_i-\frac{qd}{{\mathrm{\ϵ}}_i}x;$

Wherein, E_iThe maximum field intensity calculated for aforementioned Gauss equation, q is elementary charge unit, and E (x) is position x The electric field intensity at place, d is the thickness of x place, position layer.

The Electric Field Distribution that this step calculates has a typical feature, i.e. very big in dynode layer electric field intensity, and Absorbed layer electric field intensity is relatively small, and this characteristic makes SPAD device suppress dark counting while keeping high detection efficient.

3, avalanche probability is calculated.

Can calculate the avalanche probability of each position of dynode layer after obtaining Electric Field Distribution further, avalanche probability refers to one The probability of the multiplicative process of self-sustaining formula is caused in electronics or hole, and formula is as follows:

$\frac{{\mathrm{dP}}_e}{dx}=(1-P_e){\mathrm{\α}}_e\[P_e+P_h-P_e\·P_h\];$

$\frac{{\mathrm{dP}}_h}{dx}=-(1-P_h){\mathrm{\α}}_h\[P_e+P_h-P_e\·P_h\];$

In above formula, P_eWith P_hIt is respectively electronics and x' position in near-infrared single photon avalanche optoelectronic diode dynode layer, hole Put the probability of triggering avalanche, α_eWith α_hIt is respectively electronics and hole x' in near-infrared single photon avalanche optoelectronic diode dynode layer The ionization coefficient of position；

Then general to x' location triggered snowslide in near-infrared single photon avalanche optoelectronic diode dynode layer of electronics and hole Rate P_b(x') it is:

P_b(x')=1-(1-p_e(x'))(1-p_h(x'))；

Above-mentioned ionization coefficient α_eWith α_hCalculate according to electric field intensity:

${\mathrm{\α}}_h(F,T)=\frac{F}{E_{th\_h}}\exp (-\frac{E_{th\_h}}{\frac{{\left({\mathrm{F\λ}}_h\right)}^2}{3E_{P_h}}+{\mathrm{F\λ}}_h+kT});$

${\mathrm{\α}}_e(F,T)=\frac{F}{E_{th\_e}}\exp (-\frac{E_{th\_e}}{\frac{{\left({\mathrm{F\λ}}_e\right)}^2}{3E_{P_e}}+{\mathrm{F\λ}}_e+kT})(c_{e}T+d_e);$

Wherein, F is the electric field intensity of near-infrared single photon avalanche optoelectronic diode dynode layer, and k is that Boltzmann is normal Number, T is predetermined work temperature；E_{th_h}=1.45eV, E_{th_e}=1.60eV,

Fig. 4 is typical avalanche probability distribution result of calculation, as can be seen from the figure an electronics in the embodiment of the present invention The probability causing snowslide with hole is entirely different, the triggering avalanche process that cavity energy is more efficient.

4, avalanche voltage is calculated.

Described avalanche voltage is the voltage under particular case, and in embodiments of the present invention, described avalanche voltage is P_e(0) =0 or P_h(W) voltage when=0, wherein, W is the gross thickness of the near-infrared single photon all layers of avalanche optoelectronic diode.

As it is shown in figure 5, along with the avalanche voltage of the increase SPAD of dynode layer thickness is consequently increased.As shown in Figure 6, along with The avalanche voltage of the rising SPAD of temperature is consequently increased.

5, detection efficient is calculated.

The process that single photon is detected by SPAD device in chronological sequence order is segmented into the following steps:

1) at the absorbed layer of device, single incident photon is absorbed and is produced pair of electrons hole pair.

2) hole of electron hole centering enters into avalanche layer after passing through graded bedding and charge layer under the effect of electric field.

3) entering into the hole of avalanche layer under the effect of highfield, colliding with lattice atoms, to produce electronics empty in ionization Cave pair, these electron holes produce new electron hole pair in the effect of electric field, ultimately form avalanche effect.

4) avalanche current that avalanche process produces i.e. is detected higher than after the threshold value of reading circuit.

First three step of said process all can have influence on detection efficient, can draw detection efficient by the Physical Process Analyses Calculating formula:

P_d=P_a·P_c·P_b

In above formula, P_aFor the absorbing probability of photon, P_bFor the probability of avalanche layer triggering avalanche, P_cRepresent that carrier (includes electricity Son and hole) collection efficiency.

Wherein, P_aCan be calculated by following formula:

P_a=(1-R) (1-exp (-α_absD')),

In formula, R is the single photon reflection coefficient on near-infrared single photon avalanche optoelectronic diode surface, α_absFor near-infrared The single-photon avalanche photoelectric diode absorbed layer absorptance to single photon, d' is the thickness of absorbed layer；

P_cRepresent the collection efficiency of carrier, owing to SPAD has electric field, single photon at absorbed layer, transition zone, charge layer Absorbed produced hole substantially can get over to dynode layer under the acceleration of electric field, supposed P without loss of generality_c=1

P_bFor the probability of avalanche layer triggering avalanche, the avalanche probability calculated the most above.

As it is shown in fig. 7, be the detection efficient change curve schematic diagram with overvoltage.

6, secret mark number is calculated.

In the embodiment of the present invention, the origin of secret mark number has following several:

1) thermogenetic dark counting.In this mechanism, valence-band electrons transits to conduction band due to thermal excitation, thus produces one To electron hole pair, the dark counting that this mechanism causes is defined as DCR_therm, its computing formula is:

${\mathrm{DCR}}_{therm}=\frac{n_i}{\mathrm{\τ}};$

In formula, n_iFor the carrier density in unit volume, τ is the life-span of carrier.

2) dark counting that directly tunnelling produces.In this mechanism, valence-band electrons is direct tunneling to lead under the effect of electric field In band, thus producing pair of electrons hole pair, the dark counting that this mechanism causes is defined as DCR_tun-dir, its computing formula is:

${\mathrm{DCR}}_{tun-dir}={\mathrm{AE}}^2\exp \left(\frac{-{\mathrm{BE}}_g^{3/2}}{E}\right);$

In formula, E is electric field intensity,m_r=2 (m_cm_lh)/(m_c+m_lh), q is elementary charge unit,For Planck's constant, E_gCan carry for material, m_cMatter for conduction band electron Amount, m_lhQuality for light hole；

3) dark counting that tunnelling causes indirectly.Due to the existence valence-band electrons elder generation tunnelling of impurity and defect in this mechanism Energy level in forbidden band, is tunneling in conduction band form electron hole pair the most again, and the dark counting that this mechanism causes is DCR_tun-trap, its computing formula is:

${\mathrm{DCR}}_{tun-trap}=\frac{{\mathrm{AE}}^2{N}_T\exp \left(\frac{-B_1{E}_{B1}^{3/2}+B_2{E}_{B2}^{3/2}}{E}\right)}{N_V\exp \exp \left(\frac{-B_1{E}_{B1}^{3/2}}{E}\right)+N_C\exp \exp \left(\frac{-B_2{E}_{B2}^{3/2}}{E}\right)}$

In formula,E_B1、E_B2It is respectively valence band and defect state Energy level difference, the energy level difference of conduction band and defect state, N_cAnd N_vRepresent conduction band and the density of states of valence band respectively.

In conjunction with above-mentioned three kinds of machine-processed contributions, its summation is the dark counting of SPAD device:

DCR=DCR_therm+DCR_tun-dir+DCR_tun-trap。

As shown in Figure 8, for dark counting with the change curve schematic diagram of overvoltage.

Through the above description of the embodiments, those skilled in the art it can be understood that to above-described embodiment can To be realized by software, it is also possible to the mode adding necessary general hardware platform by software realizes.Based on such understanding, The technical scheme of above-described embodiment can embody with the form of software product, this software product can be stored in one non-easily The property lost storage medium (can be CD-ROM, USB flash disk, portable hard drive etc.) in, including some instructions with so that a computer sets Standby (can be personal computer, server, or the network equipment etc.) performs the method described in each embodiment of the present invention.

Another embodiment of the present invention also provides for the parameter optimization platform of a kind of near-infrared single photon avalanche optoelectronic diode, This platform can be used for the method described in previous embodiment, as it is shown in figure 9, this platform specifically includes that

Structural parameters acquisition module, for obtain input near-infrared single photon avalanche optoelectronic diode at predetermined work At a temperature of structural parameters；

Electric Field Distribution and avalanche probability computing module, be used for according to structural parameters and combine Gauss equation calculating near-infrared list The Electric Field Distribution of photon avalanches photoelectric diode, and then obtain near-infrared single photon avalanche optoelectronic diode dynode layer each position Avalanche probability；

Intrinsic parameters computing module, for calculating near-infrared single photon snowslide according to the avalanche probability obtained with Electric Field Distribution The intrinsic parameters of photoelectric diode.

It should be noted that the specific implementation of function that each functional module comprised in above-mentioned platform is realized exists Each embodiment above has a detailed description, therefore has here repeated no more.

Those skilled in the art is it can be understood that arrive, for convenience and simplicity of description, only with above-mentioned each function The division of module is illustrated, and in actual application, can distribute above-mentioned functions by different function moulds as desired Block completes, and the internal structure of platform will be divided into different functional modules, to complete all or part of merit described above Energy.

The above, the only present invention preferably detailed description of the invention, but protection scope of the present invention is not limited thereto, Any those familiar with the art in the technical scope of present disclosure, the change that can readily occur in or replacement, All should contain within protection scope of the present invention.Therefore, protection scope of the present invention should be with the protection model of claims Enclose and be as the criterion.

Claims (8)

1. the parameter optimization method of a near-infrared single photon avalanche optoelectronic diode, it is characterised in that including:

Obtain the structural parameters at a temperature of predetermined work of the near-infrared single photon avalanche optoelectronic diode of input；

According to structural parameters and combine Gauss equation calculate near-infrared single photon avalanche optoelectronic diode Electric Field Distribution, and then Avalanche probability to near-infrared single photon avalanche optoelectronic diode dynode layer each position；

The intrinsic parameters of near-infrared single photon avalanche optoelectronic diode is calculated according to the avalanche probability obtained and Electric Field Distribution.

The parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode the most according to claim 1, its feature It is, described according to structural parameters and combine Gauss equation and calculate the Electric Field Distribution of near-infrared single photon avalanche optoelectronic diode Expression formula is:

$\▿\·E=\frac{\mathrm{\ρ}}{{\mathrm{\ϵ}}_i};$

Above formula becomes under one-dimensional condition:

$E\left(x\right)=E_i-\frac{qd}{{\mathrm{\ϵ}}_i}x;$

Wherein,For divergence, E is electric field intensity, and ρ is charge density, ε_iFor near-infrared single photon avalanche optoelectronic diode i-th layer The dielectric constant of material, E_iThe maximum field intensity calculated for aforementioned Gauss equation, q is elementary charge unit, and E (x) is position Putting the electric field intensity at x, d is the thickness of x place, position layer.

The parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode the most according to claim 1, its feature Being, the formula of the avalanche probability calculating near-infrared single photon avalanche optoelectronic diode dynode layer each position includes:

$\frac{{\mathrm{dP}}_e}{dx}=(1-P_e){\mathrm{\α}}_e\[P_e+P_h-P_e\·P_h\];$

$\frac{{\mathrm{dP}}_h}{dx}=-(1-P_h){\mathrm{\α}}_h\[P_e+P_h-P_e\·P_h\];$

In above formula, P_eWith P_hIt is respectively electronics to touch with x' position in near-infrared single photon avalanche optoelectronic diode dynode layer, hole Send out the probability of snowslide, α_eWith α_hIt is respectively electronics and x' position in near-infrared single photon avalanche optoelectronic diode dynode layer, hole The ionization coefficient at place；

Then electronics and hole are to the probability P of x position triggering avalanche in near-infrared single photon avalanche optoelectronic diode dynode layer_b (x') it is:

P_b(x')=1-(1-p_e(x'))(1-p_h(x'))；

Above-mentioned ionization coefficient α_eWith α_hCalculate according to electric field intensity:

${\mathrm{\α}}_h(F,T)=\frac{F}{E_{th\_h}}\exp (-\frac{E_{th\_h}}{\frac{{\left({\mathrm{F\λ}}_h\right)}^2}{3E_{P_h}}+{\mathrm{F\λ}}_h+kT});$

${\mathrm{\α}}_e(F,T)=\frac{F}{E_{th\_e}}\exp (-\frac{E_{th\_e}}{\frac{{\left({\mathrm{F\λ}}_e\right)}^2}{3E_{P_e}}+{\mathrm{F\λ}}_e+kT})(c_{e}T+d_e);$

Wherein, F is the electric field intensity of near-infrared single photon avalanche optoelectronic diode dynode layer, and k is Boltzmann constant, and T is pre- Determine operating temperature；E_{th_h}=1.45eV,E_{th_e} =1.60eV, .

4., according to the parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode described in claim 1 or 3, it is special Levying and be, the intrinsic parameters of described near-infrared single photon avalanche optoelectronic diode includes: avalanche voltage, detection efficient and secret mark Number.

The parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode the most according to claim 4, its feature Being, described avalanche voltage is P_e(0)=0 or P_h(W) voltage when=0；Wherein, W is near-infrared single photon avalanche optoelectronic two grades Manage the gross thickness of all layers.

The parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode the most according to claim 4, its feature It is, described detection efficient P_dComputing formula be:

P_d=P_a·P_c·P_b；

Wherein, P_aFor the absorbing probability of photon, it is expressed as: P_a=(1-R) (1-exp (-α_absD')), in formula, R is that single photon exists The reflection coefficient on near-infrared single photon avalanche optoelectronic diode surface, α_absAbsorb for near-infrared single photon avalanche optoelectronic diode The layer absorptance to single photon, d' is the thickness of absorbed layer；P_c=1；P_bProbability for avalanche layer triggering avalanche.

The parameter optimization method of a kind of near-infrared single photon avalanche optoelectronic diode the most according to claim 4, its feature Being, the computing formula of described secret mark number DCR is:

DCR=DCR_therm+DCR_tun-dir+DCR_tun-trap；

Wherein:

DCR_thermThe dark counting produced for thermal excitation, computing formula is:

${\mathrm{DCR}}_{therm}=\frac{n_i}{\mathrm{\τ}};$

In formula, n_iFor the carrier density in unit volume, τ is the life-span of carrier；

DCR_tun-dirThe dark counting produced for direct tunnelling, computing formula is:

${\mathrm{DCR}}_{tun-dir}={\mathrm{AE}}^2\exp \left(\frac{-{\mathrm{BE}}_g^{3/2}}{E}\right);$

In formula, E is electric field intensity,m_r=2 (m_cm_lh)/(m_c+m_lh), q is elementary charge unit, E_gCan carry for material, m_cFor the quality of conduction band electron, m_lhFor light hole Quality；

DCR_tun-trapThe dark counting caused for indirect tunnelling, computing formula is:

${\mathrm{DCR}}_{tun-trap}=\frac{{\mathrm{AE}}^2{N}_T\exp \left(\frac{-B_1{E}_{B1}^{3/2}+B_2{E}_{B2}^{3/2}}{E}\right)}{N_V\exp \exp \left(\frac{-B_1{E}_{B1}^{3/2}}{E}\right)+N_C\exp \exp \left(\frac{-B_2{E}_{B2}^{3/2}}{E}\right)}$

In formula,E_B1、E_B2It is respectively the energy of valence band and defect state The energy level difference of differential, conduction band and defect state, N_cAnd N_vRepresent conduction band and the density of states of valence band respectively.

8. the parameter optimization platform of a near-infrared single photon avalanche optoelectronic diode, it is characterised in that this platform is used for realizing Method described in any one of claim 1-7, this platform includes:

Structural parameters acquisition module, for obtain input near-infrared single photon avalanche optoelectronic diode in predetermined work temperature Under structural parameters；

Electric Field Distribution and avalanche probability computing module, be used for according to structural parameters and combine Gauss equation calculating near-infrared single photon The Electric Field Distribution of avalanche optoelectronic diode, and then obtain the snowslide of near-infrared single photon avalanche optoelectronic diode dynode layer each position Probability；

Intrinsic parameters computing module, for calculating near-infrared single photon avalanche optoelectronic according to the avalanche probability obtained with Electric Field Distribution The intrinsic parameters of diode.