A Parameter Extraction Method for InP HEMT Nonlinear Equivalent Circuit Model

Abstract

The present invention discloses a method for extracting parameters of an InP HEMT non-linear equivalent circuit model, which is characterized by redefining the extraction method of some parameters in the EEHEMT model, specifically including: 1) extraction of small-signal equivalent circuit model parameters; 2) extraction of EEHEMT DC model parameters; 3) extraction of EEHEMT AC model parameters; 4) extraction of EEHEMT charge model parameters; 5) verification of the EEHEMT model and other steps. Compared with the prior art, the present invention does not need to be obtained by using a fitting method, making the parameter extraction process more convenient, greatly shortening the parameter extraction time, obtaining a relatively accurate simulation model, enabling workers to obtain more model parameters in the shortest time, saving the modeling cost, further improving the circuit design efficiency of indium phosphide high electron mobility field effect transistors, and having good application prospects and commercial development value.

Description

Technical Field

[0001] The present invention relates to the field of electromagnetic fields and microwave technologies, and more specifically to a method for extracting parameters of an InP HEMT nonlinear equivalent circuit model. Background Art

[0002] Indium phosphide high electron mobility field effect transistors (InP HEMTs) are currently widely used in monolithic microwave integrated circuits (MMICs) such as microwave band power amplifiers, millimeter wave band power amplifiers, terahertz band power amplifiers, or low noise amplifiers. With the continuous exploration of InP HEMT applications, establishing accurate large-signal equivalent circuit models, noise equivalent circuit models, and fast and accurate parameter extraction methods for devices is of great significance for the circuit design of InP HEMTs.

[0003] The EEHEMT model released by Agilent is a relatively accurate HEMT nonlinear empirical-based model, including a DC model, an AC model, and a charge model, used to simulate the device characteristics of HEMT devices operating under large signals. The existing parameter extraction techniques include: 1) using commercial paid software such as ICCAP, etc.; 2) using fitting algorithms to extract all model parameters; 3) directly reading some model parameters and then using fitting and optimization algorithms to extract all model parameters. Since the EEHEMT model has a large number of parameters, using the existing parameter extraction techniques requires a lot of time. Therefore, improving some parameter extraction methods so that workers can obtain more model parameters in the shortest time and save the modeling cost is crucial.

[0004] The existing EEHEMT model of the prior art needs to be obtained by using fitting methods, which makes the parameter extraction process complex and cumbersome, with a high modeling cost, takes a lot of time to obtain model parameters, and has low work efficiency, seriously restricting the circuit design of indium phosphide high electron mobility field effect transistors. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for extracting parameters of an InP HEMT nonlinear model in view of the deficiencies of the prior art. By redefining the extraction methods of some parameters in the EEHEMT model, the small-signal equivalent circuit model parameters, EEHEMT DC, AC, and charge model parameters are extracted respectively, without the need to obtain them by using fitting methods, which makes the parameter extraction process simpler, ensures the accuracy of the model, greatly shortens the parameter extraction time, obtains a relatively accurate simulation model, enables workers to obtain more model parameters in the shortest time, saves the modeling cost, further improves the circuit design efficiency of indium phosphide high electron mobility field effect transistors, and has good application prospects and commercial development value.

[0006] The object of the present invention is achieved as follows: A method for extracting parameters of an InP HEMT non-linear equivalent circuit model, characterized by redefining the extraction methods of some parameters in the EEHEMT model, and respectively extracting the small-signal equivalent circuit model parameters, EEHEMT DC, AC and charge model parameters. The specific extraction methods include:

[0007] 1) According to the S-parameter test data of the InP HEMT device, extract the parasitic element parameters and intrinsic element parameters.

[0008] 2) According to the I-V curve test data of the InP HEMT device, extract the EEHEMT DC model parameters.

[0009] 3) According to the S-parameter test data of the InP HEMT device under different bias conditions, obtain the variation relationship of the RF transconductance with the bias, integrate to obtain the I-V characteristics under AC, and extract the EEHEMT AC model parameters.

[0010] 4) According to the S-parameter test data of the InP HEMT device under different bias conditions, obtain the variation curve of the gate capacitance with the bias, and extract the EEHEMT charge model parameters.

[0011] The extraction of the parasitic element parameters and intrinsic element parameters according to the S-parameter test data of the InP HEMT device specifically includes:

[0012] 1-1: According to the S-parameters of the open-circuit test structure of the InP HEMT device obtained by testing, convert them into Y-parameters to obtain the values of the gate parasitic capacitance C pg , drain parasitic capacitance C pd and gate-drain parasitic capacitance C pgd . The gate parasitic capacitance C pg is calculated by the following formula (a):

[0013]

[0014] The drain parasitic capacitance C pd is calculated by the following formula (b):

[0015]

[0016] The gate-drain parasitic capacitance C pgd is calculated by the following formula (c):

[0017]

[0018] where ω is the angular frequency; Im is used to represent taking the imaginary part of the Y-parameter; Y 11 is the input admittance in the case of the output port being short-circuited; Y 12is the reverse transfer admittance in the case of short - circuit of the input port; Y 21 is the forward transfer admittance in the case of short - circuit of the output port; Y 22 is the output admittance in the case of short - circuit of the input port.

[0019] 1 - 2: According to the S - parameters of the short - circuit test structure of the InP HEMT device obtained by testing, after de - embedding technology, they are respectively converted into Z - parameters to obtain the gate parasitic inductance L g , the drain parasitic inductance L d , the source parasitic inductance L s and the lead resistances R pg , R pd , R ps The parameter values of, the gate parasitic inductance L g is calculated by the following formula (d):

[0020]

[0021] The drain parasitic inductance L d is calculated by the following formula (e):

[0022]

[0023] The source parasitic inductance L s is calculated by the following formula (f):

[0024]

[0025] The lead resistance R p is calculated by the following formula (g):

[0026] R pg = Re(Z 11 - Z 12 ) (g);

[0027] The lead resistance R pd is calculated by the following formula (h):

[0028] R pd = Re(Z 22 - Z 12 ) (h);

[0029] The lead resistance R ps is calculated by the following formula (i):

[0030] R ps = Re(Z 12 ) = Re(Z 21 ) (i).

[0031] where, Re is used to represent taking the real part of the Z - parameter; Z11 is the input impedance when the output port is open; Z 12 is the reverse transfer impedance when the input port is open; Z 21 is the forward transfer impedance when the output port is open; Z 22 is the output impedance when the input port is open.

[0032] 1 - 3: Use the COLD - FET cutoff method to extract the gate parasitic resistance R g , drain parasitic resistance R d , source parasitic resistance R s values respectively from the following equations (j) - (l);

[0033] R g = Re(Z 11 - Z 12 ) (j);

[0034] R d = Re(Z 22 - Z 12 ) (k);

[0035] R s = Re(Z 12 ) = Re(Z 21 ) (l).

[0036] 1 - 4: According to the S - parameters measured under the normal operating state of the InP HEMT device under different bias conditions, after de - embedding and converting them into Y - parameters, and extracting them respectively from the following equations (m) - (t), the parameter values of the intrinsic components C gs , C gd , C ds , R i , g ds , g m , τ are obtained:

[0037]

[0038]

[0039]

[0040] g m = |Y 21 - Y 12 | (p);

[0041]

[0042]

[0043]

[0044] Among them, C gd is the gate-drain intrinsic capacitance; C ds is the drain-source intrinsic capacitance; C gs is the gate-source intrinsic capacitance; g m is the transconductance; R ds is the drain output resistance; R i is the intrinsic channel resistance; τ is the time delay; b is the intermediate variable represented by the following formula (u):

[0045]

[0046] Extracting the DC model parameters of the EEHEMT according to the I-V curve test data of the InP HEMT device specifically includes:

[0047] 2-1: Determining V dso according to the gds / gm-Vgs curve under different biases, and determining the γ and V ch parameter values according to the slope and intercept of the curve. When V ds = V dso and V gs > V to :

[0048] 2-2: Directly extracting V ds = V dso when g m -V gs curves, and directly extracting V go 、V co 、g mMAX .

[0049] 2-3: According to the transfer characteristic curve, the gate-source bias voltage when I ds = 10 μA is V to .

[0050] 2-4: Extracting the parameter κ according to the I-V characteristic curve, that is, the I ds value calculated by the following formula (v):

[0051]

[0052] Among them, κ is the output conductance parameter; I ds is the drain current; I dso is the saturation drain current; V sat is the saturation drain voltage.

[0053] Extracting the AC model parameters of the EEHEMT according to the S-parameter test data of the InP HEMT device under different bias conditions specifically includes:

[0054] 3-1: Based on the extracted intrinsic transconductance parameter value, which is the radio frequency transconductance, plot the variation of the radio frequency transconductance with the bias, and after integrating it, obtain the I-V characteristic curve of the device under the AC condition.

[0055] 3-2: Similar to the DC model parameter extraction process in the above steps 2-1 to 2-4, obtain the AC model parameters V toac , g mMAXac , κ ac and γ ac .

[0056] Based on the S-parameter test data of the InP HEMT device under different bias conditions, obtain the curve of the gate capacitance varying with the bias, and extract the EEHEMT charge model parameters, specifically including:

[0057] 4-1: De-embed the S-parameters obtained from the tests of the InP HEMT device under different bias conditions, convert them into Y-parameters, extract the input capacitance C 11 , transfer capacitance C 12 parameter values, plot their variation with the bias. The input capacitance C 11 is calculated by the following formula (w):

[0058]

[0059] The transfer capacitance C1 is calculated by the following formula (x):

[0060]

[0061] where the subscript int represents the intrinsic network.

[0062] 4-2: Directly extract the C 11o , C 11th , Δgs, V infl , Δds, C 12sat , C gdsat parameter values according to the relationship between the gate charge and the bias in the following formula (y), and calculate λ;

[0063]

[0064] where λ is defined as the slope of the C 11 -V ds curve; V infl is the gate-source voltage when C 11 reaches the maximum; C 11th is the minimum input capacitance when V ds =V dso ; C 11o is the minimum input capacitance when V ds =V dsoThe maximum input capacitance at

[0065] Compared with the prior art, the present invention has a simpler parameter extraction process, ensures the accuracy of the model, and can obtain the small-signal equivalent circuit model parameters, EEHEMT DC, AC, and charge model parameters with high precision without using the fitting method, greatly shortening the parameter extraction time, obtaining a more accurate simulation model, enabling workers to obtain more model parameters in the shortest time, saving the modeling cost, further improving the circuit design efficiency of indium phosphide high electron mobility field effect transistors, and having good application prospects and commercial development value. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 It is a flowchart of the present invention;

[0067] Figure 2 It is a small-signal equivalent circuit model of InP HEMT device;

[0068] Figure 3 It is a flowchart for extracting small-signal equivalent circuit model parameters of InP HEMT device;

[0069] Figure 4 It is an equivalent circuit model of the open-circuit test structure corresponding to step S101 of the present invention;

[0070] Figure 5 It is the gate parasitic capacitance C of InP HEMT device pg Extraction result diagram;

[0071] Figure 6 It is the drain parasitic capacitance C of InP HEMT device pd Extraction result diagram;

[0072] Figure 7 It is the gate-drain parasitic capacitance C of InP HEMT device pg Extraction result diagram;

[0073] Figure 8 It is an equivalent circuit model of the short-circuit test structure;

[0074] Figure 9 It is the source parasitic inductance L of InP HEMT device s Extraction result diagram;

[0075] Figure 10 It is the gate parasitic inductance L of InP HEMT device g Extraction result diagram;

[0076] Figure 11 It is the drain parasitic inductance L of InP HEMT device d Extraction result diagram;

[0077] Figure 12 It is the graph of the lead resistance extraction result of the InP HEMT device;

[0078] Figure 13 It is the equivalent circuit model under the cut-off condition of the COLD-FET;

[0079] Figure 14 It is the graph of the parasitic resistance extraction result of the InP HEMT device;

[0080] Figure 15 It is the circuit diagram of the intrinsic network in the small-signal equivalent circuit model of the InP HEMT device;

[0081] Figure 16 It is the extraction result of the intrinsic capacitance of the InP HEMT device;

[0082] Figure 17 It is the intrinsic transconductance parameter g of the InP HEMT device m extraction result;

[0083] Figure 18 It is the intrinsic resistance R of the InP HEMT device ds extraction result;

[0084] Figure 19 It is the intrinsic resistance R of the InP HEMT device i extraction result;

[0085] Figure 20 It is the extraction result of the time delay parameter τ of the InP HEMT device;

[0086] Figure 21 It is the flowchart of the DC model parameter extraction of the EEHEMT;

[0087] Figure 22 It is the curve of extracting partial DC model parameter values of the present invention;

[0088] Figure 23 It is the I-V characteristic curve of the InP HEMT device;

[0089] Figure 24 It is V ds =V dso When testing, the g of the InP HEMT device m -V gs curve;

[0090] Figure 25 It is the g of the InP HEMT device under AC conditions m -V gs curve;

[0091] Figure 26 For the g of InP HEMT device under AC conditions ds -V ds curve;

[0092] Figure 27 For the I-V characteristic curve of InP HEMT device under AC conditions;

[0093] Figure 28 For the flowchart of EEHEMT charge model parameter extraction of InP HEMT device;

[0094] Figures 29 - 32 They are respectively the curves of gate charge of InP HEMT device varying with bias;

[0095] Figure 33 For the comparison chart of I-V characteristics between the model of the present invention and test data;

[0096] Figure 34 For the model of the present invention and g in test data m -V gs comparison chart;

[0097] Figure 35 For the comparison chart of S parameters between the model of the present invention and test data. Specific implementation manners

[0098] To make the purpose, parameter extraction method and advantages of the present invention more clear, the following will clearly and completely describe the parameter extraction method of the present invention in combination with specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in 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.

[0099] Embodiment 1

[0100] The following describes the specific implementation steps and methods of the present invention in combination with the drawings.

[0101] Refer to Figure 1 , the flowchart of the EEHEMT nonlinear equivalent circuit model parameter extraction method based on InP HEMT device in this embodiment, and this method includes the following steps:

[0102] Step S100: Extract small-signal equivalent circuit model parameters;

[0103] Step S200: Extract EEHEMT DC model parameters;

[0104] Step S300: Extract EEHEMT AC model parameters;

[0105] Step S400: Extract the EEHEMT charge model parameters;

[0106] Step S500: Verify the EEHEMT model.

[0107] Refer to Figure 2 , considering that the small-signal equivalent circuit model is the basis for constructing the large-signal equivalent circuit model, it is very necessary to extract the parameters of the small-signal equivalent circuit model; before step S100, first select the small-signal equivalent circuit model of the InP HEMT device.

[0108] Refer to Figure 3 , the specific steps of the said step S100 include the following steps:

[0109] Step S101: Use the open-circuit test structure method to extract the parasitic capacitances (C pg , C pd , C pgd );

[0110] Step S102: Use the short-circuit test structure method to extract the parasitic inductances (L g , L d , L s );

[0111] Step S103: Use the COLD-FET reverse cut-off method to extract the parasitic resistances (R g , R d , R s );

[0112] Step S104: After de-embedding the S-parameters of the device measured under the normal working state, convert them into the intrinsic Y-parameters, and extract the parameter values of the intrinsic components (C gs , C gd , C ds , R i , g ds , g m , τ).

[0113] Refer to Figure 4 , for the open-circuit test in the said step S101, the Y-parameters corresponding to the two-port network are expressed by the following equations (1) to (3):

[0114] Y 11 = jω(C pg + C pgd ) (1);

[0115] Y 12 = Y 21 = -jωC pgd (2);

[0116] Y 22= jω(C pd + C pgd ) (3).

[0117] Therefore, the parasitic capacitances Cpg, Cpd, and Cpgd are calculated by the following equations (a) to (c), respectively:

[0118]

[0119]

[0120]

[0121] Refer to Figures 5 - 7 , the parasitic capacitance C pg , C pd , C pgd . The parameter extraction results of the parasitic capacitances reflect that the PAD capacitance of the HEMT is independent of frequency under low-frequency conditions. Therefore, the PAD capacitance value is the average capacitance value when the frequency is lower than 25 GHz.

[0122] Refer to Figure 8 , for the short-circuit test in step S102, after de-embedding the parasitic PAD capacitance, the Z parameters corresponding to the two-port network are expressed by the following equations (4) to (6):

[0123] Z 11 = jω(L g + L s ) + R pg + R ps (4);

[0124] Z 12 = Z 21 = jωL s + R ps (5);

[0125] Z 22 = jω(L d + L s ) + R pd + R ps (6).

[0126] Therefore, the parasitic inductances L g , L d , L s and the lead resistances R pg , R pd , R ps are calculated by the following equations (d) to (i), respectively:

[0127]

[0128]

[0129]

[0130] R pg = Re(Z 11 - Z 12 )(g);

[0131] R pd = Re(Z 22 - Z 12 )(h);

[0132] R ps = Re(Z 12 ) = Re(Z 21 )(i).

[0133] Wherein, Re is used to represent taking the real part of the Z parameter; Z 11 is the input impedance when the output port is open; Z 12 is the reverse transfer impedance when the input port is open; Z 21 is the forward transfer impedance when the output port is open; Z 22 is the output impedance when the input port is open.

[0134] Refer to Figures 9 - 11 , the parameter extraction results of the parasitic inductors L g , L d , L s reflect that the parasitic effects caused by the PAD capacitance of the device are significant at high frequencies. Therefore, the parameter values of the parasitic inductors L g , L d , L s should be extracted at low frequencies.

[0135] Refer to Figure 12 , the parameter extraction results of the lead resistors R pg , R pd , R ps show that the extraction results of the lead resistors are all less than 1 Ω and can be absorbed by the parasitic resistors R g , R d , R s . Therefore, the lead resistors R pg , R pd , R ps are not considered in the subsequent modeling.

[0136] Refer to Figure 13 , in the step S103, the bias condition of the COLD-FET cutoff method is: V g < V to , V d= Vs = 0 V, the equivalent circuit of the InP HEMT device consists of 9 parasitic elements and 3 intrinsic capacitors (C gsp , C gdp , C dsp ) under the cut-off condition.

[0137] After de-embedding the measured S-parameters under the COLD-FET cut-off condition from the parasitic PAD capacitance and parasitic inductance in turn, only the elements inside the dashed box remain in the circuit, where the parasitic resistors R g , R d , R s determine the real part of the Z-parameters of this two-port network, and the intrinsic capacitance determines the imaginary part of the Z-parameters.

[0138] Regarding the 3 parasitic resistors and the intrinsic capacitance as a T-type network, the real part of the Z-parameters of this network is expressed by the following equations (7) to (9):

[0139] Re(Z 11 ) = R g + R s (7);

[0140] Re(Z 12 ) = Re(Z 21 ) = R s (8);

[0141] Re(Z 22 ) = R d + R s (9).

[0142] Therefore, the parasitic resistors are extracted and calculated by the following equations (j) to (l):

[0143] R g = Re(Z 11 - Z 12 ) (j);

[0144] R d = Re(Z 22 - Z 12 ) (k);

[0145] R s = Re(Z 12 ) = Re(Z 21 ) (l).

[0146] Referring to Figure 14 , the extraction results of the parasitic resistors show that R g fluctuates less with frequency, R d can be approximated as a straight line at high frequencies, but R s fluctuates the most with frequency and shows negative resistance at high frequencies; therefore, taking Rs The initial value is set to: R s0 = R d0 , and the initial parameter values of the parasitic elements are shown in the parasitic element extraction results in Table 1 below:

[0147] Table 1 Parasitic Element Extraction Results

[0148]

[0149] Refer to Figure 15 , in step S104, the S-parameters of the InP HEMT device measured under normal operating conditions are eliminated for the parasitic elements to obtain the small-signal intrinsic network equivalent circuit of the InP HEMT device. According to the definition of Y-parameters, the Y-parameters of this two-port network are calculated by the following equations (10) to (13):

[0150]

[0151] Y 12 = -jωC gd , (11);

[0152] Y 21 = -jωC gd + g m e -jωτ (12);

[0153] Y 22 = jω(C gd + C ds ) + R ds (13).

[0154] The intrinsic elements can be calculated by the following equations (m) to (u) using the above equations (10) to (13):

[0155]

[0156]

[0157]

[0158] g m = |Y 21 - Y 12 | (p);

[0159]

[0160]

[0161]

[0162]

[0163] Among them, C gd is the gate-drain intrinsic capacitance; C ds is the drain-source intrinsic capacitance; C gs is the gate-source intrinsic capacitance; g m is the transconductance; R ds is the drain output resistance; R i is the intrinsic channel resistance; τ is the time delay; b is an intermediate variable.

[0164] Refer to Figures 16 - 20 , since the intrinsic components are related to the bias, the intrinsic components need to be extracted under fixed bias conditions. When the bias conditions are V ds = 1V and V gs = 0V, it can be seen from the extraction results of the intrinsic component parameters obtained through step S104 that when the frequency is lower than 40 GHz, the fluctuation of the intrinsic components with the frequency is relatively small and can be regarded as independent of the frequency.

[0165] When V ds = 1V and V gs = 0V, the values of the intrinsic component parameters are shown in the extraction results in Table 2 below:

[0166] Table 2 Extraction Results of Intrinsic Components

[0167]

[0168] Refer to Figure 21 : The specific steps of step S200 include the following steps:

[0169] Step S201: Extract the parameter values of V dso , γ, and V ch

[0170] Refer to Figure 22 , according to the formulas of g ds and g m in the EEHEMT model, when V ds = V dso and V gs > V to , the ratio of g ds to g m shows a linear negative correlation with the gate-source bias voltage V gs .

[0171] Extract V ds according to the functional relationship of the g ds / g m - V gs curve in the interval of V gs > V to dso, where g ds / g m can be calculated by the following formula (14):

[0172]

[0173] Preferably, g ds / g m -V gs The slope of the curve is -γ, and g ds / g m -V gs The intercept of the curve is γ×V ch .

[0174] Step S202: Directly extract some DC model parameters

[0175] When V ds =V dso , according to the physical meaning of the parameters, the parameter values of V sat , V to , V go , V co , g mMAX can be directly extracted. The physical meanings of some DC model parameters are shown in Table 3 below:

[0176] Table 3 Physical meanings of some DC model parameters

[0177]

[0178] Step S203: Calculate the κ parameter value according to the formula

[0179] When the gate bias is relatively large, according to the internal formula I of the EEHEMT model ds needs to be transformed according to the following formula (v):

[0180]

[0181] where I dso is the saturation drain current. When V ds >V dso , The output conductance parameter κ can be simplified and calculated by the following formula (15):

[0182]

[0183] Refer to Figures 23 - 24 , the I-V characteristic curve of the InP HEMT device and the transconductance vs. bias variation curve (g ds =V dso ) of the InP HEMT device measured when m -V gsThe curve) can determine the DC model parameter values of EEHEMT through steps S202 and S203. The extraction results are shown in Table 4 below:

[0184] Table 4 EEHEMT DC Model Parameter Extraction Results

[0185]

[0186] The specific steps of step S300 are as follows:

[0187] Step S301: Obtain the I-V characteristic curve under AC conditions according to the gm-Vgs curve under AC conditions.

[0188] Refer to Figures 25 - 26 , and extract the g m , g ds parameter values under different bias conditions according to the method provided in step S104, and obtain the variation relationships of AC transconductance and AC output conductance with bias.

[0189] Refer to Figure 27 , and integrate the AC transconductance with respect to the gate-source bias voltage to obtain the I-V characteristic curve under AC conditions.

[0190] Step S302: Similar to the DC model parameter extraction process of steps S201 - S203, obtain the parameter values of the AC model parameters (V toac , g mMAXac , κ ac , γ ac ). The extraction results are shown in Table 5 below:

[0191] Table 5 EEHEMT AC Model Parameter Extraction Results

[0192]

[0193] Refer to Figure 28 , the specific steps of step S400 are as follows:

[0194] Step S401: Calculate the variation relationships of the input capacitance C 11 and the transfer capacitance C 12 with bias

[0195] Using the intrinsic Y parameters under different bias conditions obtained in step S104, the input capacitance C 11 and the transfer capacitance C 12 are calculated by the following equations (w) - (x):

[0196]

[0197]

[0198] Among them, the subscript int represents the intrinsic network.

[0199] Step S402: Directly extract some parameter values of the EEHEMT charge model

[0200] Refer to Figures 29 - 32 , and directly extract C according to the physical meanings of some parameters of the EEHEMT charge model 11o , C 11th , Δgs, V infl , Δds, C 12sat , C gdsat . The physical meanings of some parameter values of the EEHEMT charge model are shown in Table 6 below:

[0201] Table 6 Physical Meanings of Some Parameter Values of the EEHEMT Charge Model

[0202]

[0203] Step S403: Extract the λ parameter value

[0204] According to the following equation (y) for the relationship between the input capacitance C 11 and the voltage:

[0205]

[0206] where λ is the slope of the C 11 -V ds curve; V infl is the gate-source voltage when C 11 reaches its maximum;

[0207] C 11th is the minimum input capacitance when V ds =V dso ; C 11o is the maximum input capacitance when V ds =V dso .

[0208] Under the fixed bias condition, the λ parameter value can be extracted. The EEHEMT charge model parameter values obtained through steps S401 - S403 are shown in the extraction results in Table 7 below:

[0209] Table 7 EEHEMT Charge Model Parameter Extraction Results

[0210]

[0211] In step S500, it is necessary to build an equivalent circuit of the InP HEMT device in the ADS software and call the EEHEMT model, input all the parameter values extracted through steps S100 - S400, and obtain the simulation results of the model.

[0212] Refer to Figures 33 - 35 , according to the comparison results of the I-V characteristic curve, transconductance change curve, and S-parameters between the test data and the simulation results. Based on the test data and simulation results of the I-V characteristic curve, the relative error value is calculated to be 4.371%. The S-parameter error analysis is calculated according to the following formulas (16) to (17):

[0213]

[0214]

[0215] After calculation, the error between the simulation results and the test data of the S-parameters of the EEHEMT model obtained by the present invention is 8.14%. The comparison results show that while ensuring the model accuracy, the present invention redefines the extraction method of some parameters in the EEHEMT model, making the parameter extraction process more convenient and cost-saving.

[0216] The above embodiments further describe the present invention in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope protected by the claims of the present invention, and all of them fall within the protection scope of the present invention.

Claims

1. A method for extracting parameters of an InP HEMT non-linear equivalent circuit model, characterized in that The method specifically includes the following steps: S100: Extraction of small-signal equivalent circuit model parameters According to the S-parameter test data of the InP HEMT device, extract the parasitic element parameters and intrinsic element parameters; Step S200: Extraction of EEHEMT DC model parameters According to the I-V curve test data of the InP HEMT device, extract the EEHEMT DC model parameters; S300: Extraction of EEHEMT AC model parameters According to the S-parameter test data of the InP HEMT device under different bias conditions, obtain the variation relationship of the radio frequency transconductance with the bias, integrate to obtain the I-V characteristics under AC, and according to the I-V characteristic curve test data, extract the EEHEMT AC model parameters; S400: Extraction of EEHEMT charge model parameters According to the S-parameter test data of the InP HEMT device under different bias conditions, obtain the variation curve of the gate capacitance with the bias, and extract the EEHEMT charge model parameters according to the variation curve; S500: Verification of the EEHEMT model Build an equivalent circuit of the InP HEMT device in the ADS software, call the EEHEMT model, input the small-signal equivalent circuit model parameters, EEHEMT DC, AC and charge model parameter values extracted in the above steps, and obtain the simulation results of the model; The extraction of the small-signal equivalent circuit model parameters specifically includes: 1-1: According to the S-parameters of the open-circuit test structure of the InP HEMT device obtained from the test, convert them into Y-parameters to obtain the gate parasitic capacitance C pg , the drain parasitic capacitance C pd and the gate-drain parasitic capacitance C pgd . The value of the gate parasitic capacitance C pg is calculated by the following formula (a): ； The drain parasitic capacitance C pd is calculated by the following formula (b): ； The gate-drain parasitic capacitance C pgd is calculated by the following formula (c): ； Among them, is the angular frequency; is used to represent taking the imaginary part of the Y parameter; is the input admittance under the condition that the output port is short-circuited; is the reverse transfer admittance under the condition that the input port is short-circuited; is the forward transfer admittance under the condition that the output port is short-circuited; is the output admittance under the condition that the input port is short-circuited; 1-2: According to the S parameters of the short-circuit test structure of the InP HEMT device obtained from the test, after the de-embedding technique, they are respectively converted into Z parameters to obtain the gate parasitic inductance L g , the drain parasitic inductance L d , the source parasitic inductance L s and the lead resistances R pg , R pd , R ps of the parameter values. The gate parasitic inductance L g is calculated by the following formula (d): ； The drain parasitic inductance L d is calculated by the following equation (e): ； The source parasitic inductance L s is calculated by the following formula (f): ； Lead resistance R p Calculated by the following formula (g): ； The lead resistance R pd is calculated by the following formula (h): ； The lead resistance R ps is calculated by the following formula (i): ； Among them, is used to represent the real part of the Z parameter; is the input impedance when the output port is open; is the reverse transfer impedance when the input port is open; is the forward transfer impedance when the output port is open; is the output impedance when the input port is open; 1-3: Using the COLD-FET cut-off method, the gate parasitic resistance R, the drain parasitic resistance R, and the source parasitic resistance R are extracted from the following equations (j) to (l), respectively; g and the drain parasitic resistance R d and the source parasitic resistance R s values; ； ； ； 1-4: The S-parameters obtained from the normal operating state of the InP HEMT device under different bias conditions are de-embedded, converted into Y-parameters, and extracted by the following equations ( ) to ( ) respectively, and the parameter values of the intrinsic components C gd , C ds , C gs , , R i , and τ are obtained: ； ； ； ； ； ； ； Among them, C gd is the gate-drain intrinsic capacitance; C ds is the drain-source intrinsic capacitance; C gs is the gate-source intrinsic capacitance; is the transconductance; is the drain output resistance; is the intrinsic channel resistance; τ is the time delay; the intermediate variable b is represented by the following formula (u): 。 2. The method for extracting parameters of the InP HEMT nonlinear equivalent circuit model according to claim 1, characterized in that The extraction of the EEHEMT DC model parameters specifically includes: 2-1: Determine V according to the gds / gm-Vgs curves under different biases dso , and determine γ and V respectively according to the slope and intercept of the curve ch parameter values. When V ds = V dso and V gs > V to , ; where V ds is the source-drain voltage, V gs is the gate-source voltage, γ is defined as the change factor of the threshold voltage with respect to the source-drain voltage, V ch is defined as the source-drain voltage when γ does not change with the I-V curve, V dso is defined as the source-drain voltage when the output voltage is zero, and V to is the threshold voltage; 2-2: According to V ds =V dso when g m -V gs curve, directly extract V go 、V co 、g mMAX ; Among them, V go is defined as the gate-source voltage at maximum transconductance, V co is defined as the gate-source voltage when the transconductance drops, g mMAX is defined as the maximum transconductance; 2-3: According to the transfer characteristic curve, when I ds = 10 μA, the gate-source bias voltage is V to ; 2-4: According to the I-V characteristic curve, extract the parameter κ, which is the value calculated by the following formula (v): value ； where κ is the output conductance parameter; is the drain current; is the saturated drain current; is the saturated drain voltage.

3. A method for extracting parameters of an InP HEMT nonlinear equivalent circuit model according to claim 1, characterized in that The extraction of the EEHEMT AC model parameters specifically includes: 3-1: C extracted according to step S100 gs and C gd and C ds and R i and g ds and g m Based on the intrinsic component parameter values of τ, plot the variation of radio frequency transconductance with bias, and after integrating it, obtain the I-V characteristic curve of the device under the AC state; 3-2: Similar to the DC model parameter extraction process of EEHEMT, the AC model parameters V toac , g mMAXac , κ ac , γ ac are obtained.

4. A method for extracting parameters of an InP HEMT non-linear equivalent circuit model according to claim 1, characterized in that The extraction of the EEHEMT charge model parameters specifically includes: 4-1: De-embed the S-parameters obtained from the tests of InP HEMT devices under different bias conditions, convert them to Y-parameters, and extract the input capacitance C 11 , transfer capacitance C 12 parameter values, and plot their variation with bias. The input capacitance C 11 is calculated by the following equation (w): ； The transfer capacitance C1 is calculated by the following ([[]] [[]]) formula: ) ； Among them, the subscript represents the eigen network; 4-2: According to the relationship between gate charge and bias in the following ([[]] [[]]) formula, directly extract the values of C , C 11o , C 11th , Δgs, V infl , Δds, C 12sat , C gdsat parameter values, and calculate λ; ; where λ is defined as C 11 -V ds the slope of the curve; is the minimum input capacitance when V ds =V dso ; is the maximum input capacitance when V ds =V dso .

Images