A modeling method for a large signal model of a GaN-HEMT device

Abstract

The modeling method of the large signal model of the GaN-HEMT device provided by the present invention includes: performing a pulse current-voltage test on the GaN-HEMT device in a high and low temperature environment to obtain current-voltage data at different temperatures; using an improved drain current formula to build a leakage model of the GaN-HEMT device, wherein the improved drain current formula includes parameters related to the ambient temperature; fitting the current-voltage data at different temperatures with the leakage model to determine the parameters of the leakage model. Since the improved drain current formula includes parameters related to the ambient temperature, a large signal model including parameters related to the ambient temperature can be established, so that a large signal model that accurately predicts the performance of the GaN-HEMT device in a high and low temperature environment can be obtained, thereby improving the accuracy of the GaN-HEMT device simulation model.

Description

Technical Field

[0001] The present invention relates to the technical field of power devices, and more specifically to a modeling method for a large signal model of a GaN-HEMT device. Background Art

[0002] High Electron Mobility Transistor (HEMT) has broad application prospects in the field of microwave power due to its advantages such as good high-frequency performance and low on-resistance. In order to establish the connection between process parameters and device microwave characteristics, and thus analyze process stability and circuit yield, it is very necessary to establish a simulation model of HEMT devices.

[0003] However, the traditional thermoelectric model only considers the self-heating model, and does not consider the high and low temperature model, resulting in poor accuracy of the HEMT device simulation model. Especially for GaN-HEMT devices, their electron mobility and saturation velocity are greatly affected by the channel temperature, and the size of the channel temperature depends not only on the size of the device power consumption, but also on the change of ambient temperature. Therefore, it is crucial to establish a large signal model that can accurately predict the performance of GaN-HEMT devices in high and low temperature environments for power circuit analysis and high-quality design. Summary of the invention

[0004] In view of this, the present invention provides a modeling method for a large signal model of a GaN-HEMT device to improve the accuracy of the simulation model of the GaN-HEMT device in high and low temperature environments.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A modeling method for a large signal model of a GaN-HEMT device, comprising:

[0007] Conduct pulse current-voltage tests on GaN-HEMT devices in high and low temperature environments to obtain current-voltage data at different temperatures;

[0008] The improved drain current formula is used to build a leakage model of the GaN-HEMT device, wherein the large signal model includes the leakage model, and the improved drain current formula includes parameters related to the ambient temperature;

[0009] The current-voltage data at different temperatures are fitted with the leakage model to determine the parameters of the leakage model.

[0010] Optionally, the pulse current-voltage test of the GaN-HEMT device under high and low temperature environment includes:

[0011] Setting the ambient temperature of the GaN-HEMT device to different temperatures within a preset temperature range;

[0012] At any temperature, a pulse current-voltage test is performed on the GaN-HEMT device to obtain current-voltage data.

[0013] Optionally, the preset temperature range includes 25°C-175°C, and different temperatures within the preset temperature range include 25°C, 50°C, 75°C, 100°C, 125°C, 150°C and 175°C.

[0014] Optionally, when performing a pulse current-voltage test, the pulse width ranges from 200 ns to 300 ns, the period ranges from 200 μm to 300 μm, and the duty cycle ranges from 0.1% to 0.2%.

[0015] Optionally, the improved drain current formula is: I ds -F g *F d *G md *i dss ;

[0016] in,

[0017] V p =V p0 +V φ +P*V ds ; W th =w0+w1*T j ; G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm )));

[0018] T j It is a parameter related to the ambient temperature.

[0019] Optionally, the improved drain current formula is: I ds =F g *F d *G md *i dssth ;

[0020] in,

[0021] V p =V p0 +Vφ +P*V ds ;

[0022] G md =1+β gm d*(V ds -V dm )*(1+tanh(α gm d*(V gs -V gm )));

[0023]

[0024] T j It is a parameter related to the ambient temperature.

[0025] Optionally, the improved drain current formula is: I ds =F g *F d *G md *i dss ;

[0026] in,

[0027] V p =V p0 +V φ +P*V ds ;

[0028] G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm )));

[0029] T j It is a parameter related to the ambient temperature.

[0030] Optionally, the improved drain current formula is: I ds =F g *F d *G md *i dssth ;

[0031] in,

[0032]

[0033] V p =V p0 +Vφ +P*V ds ; W th =w0+w1*T j ;

[0034] G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm )));

[0035]

[0036] T j It is a parameter related to the ambient temperature.

[0037] Optionally, the improved drain current formula is used to construct a leakage model of the GaN-HEMT device, including:

[0038] Write the improved drain current formula into the second port formula of the symbol definition device in the Agilent RFIC design software to build a leakage model of the GaN-HEMT device using the symbol definition device in the Agilent RFIC design software;

[0039] The symbol definition device includes three ports, the first port is the input port of the gate voltage, the second port is the source-drain channel port, and the third port is the input port of the ambient temperature.

[0040] Optionally, fitting the current-voltage data at different temperatures with the leakage model to determine parameters of the leakage model includes:

[0041] Fitting the current-voltage data at room temperature with the leakage model to determine parameters in the leakage model that are independent of temperature;

[0042] The current-voltage data at other temperatures are fitted to the leakage model to determine the temperature-related parameters in the leakage model.

[0043] Compared with the prior art, the technical solution provided by the present invention has the following advantages:

[0044] The modeling method of the large signal model of the GaN-HEMT device provided by the present invention, since the improved drain current formula includes parameters related to the ambient temperature, the improved drain current formula is used to build the leakage model of the GaN-HEMT device, and the current-voltage data at different temperatures are fitted with the leakage model. After the parameters of the leakage model are determined, a large signal model including parameters related to the ambient temperature can be established, so that a large signal model that accurately predicts the performance of the GaN-HEMT device in high and low temperature environments can be obtained, thereby improving the accuracy of the GaN-HEMT device simulation model. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0046] Figure 1 A flow chart of a method for modeling a large signal model of a GaN-HEMT device provided by one embodiment of the present invention;

[0047] Figure 2 A topological structure diagram of a large signal model of a GaN-HEMT device provided by one embodiment of the present invention;

[0048] Figure 3 A schematic diagram of an SDD device provided by one embodiment of the present invention;

[0049] Figures 4 to 10 The following are comparison charts of model simulation data and measured data at 25℃, 50℃, 75℃, 100℃, 125℃, 150℃ and 175℃ respectively. DETAILED DESCRIPTION

[0050] The above is the core idea of ​​the present invention. In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] The embodiment of the present invention provides a modeling method for a large signal model of a GaN-HEMT device, such as Figure 1 As shown, including:

[0052] S101: Perform pulse current-voltage test, i.e. pulse IV test, on GaN-HEMT devices in high and low temperature environments to obtain current-voltage data at different temperatures;

[0053] In some embodiments of the present invention, the topological structure of the large signal model of the GaN-HEMT device is as follows: Figure 2 As shown, it includes the thermoelectric model, that is, Figure 2 Thermionic networks in the device are usually described in the form of thermal electron networks or thermal subcircuits to describe the temperature changes caused by the self-heating effect of the device, and are fed back to the nonlinear drain-source current to form a nonlinear feedback loop. The numerical iterative solution eventually reaches stability.

[0054] It should be noted that the large signal model is established on the basis of the small signal model. In other words, if you want to establish a large signal model, you must first establish a small signal model. The establishment of the small signal model mainly includes the extraction of parasitic parameters and intrinsic parameters, such as Figure 2 As shown, the parasitic parameters are: parasitic capacitance (Cpg, Cpd), parasitic resistance and inductance (Rg, Rd, Rs, Lg, Ld, Ls), intrinsic parameters: Ri, Cds, τ, Gm, Gd, Cgs, Cgd, Rgd.

[0055] The process of extracting parasitic parameters and intrinsic parameters includes: firstly, testing S parameters, the test conditions are frequency 0-20GHz, bias conditions (-1.6V, 28V), scanning range is Vg (-4, 2), step is 0.5, Vd (0, 48), step is 1. Then, IVCAD software is used to extract the intrinsic parameters and parasitic parameters in the small signal model.

[0056] The establishment of the large signal model mainly considers the establishment of the nonlinear Ids model and the Cgs model, Cgd model, and gate leakage model. Finally, the relevant parameters are determined through measured data and simulation fitting, and the model is finally verified. Specifically, the charge model provided by the IVCAD software can be used to extract the capacitance parameters in Cgs and Cgd. The gate leakage model provided by the IVCAD software is used to fit the gate leakage current and extract the relevant parameters of the leakage model.

[0057] The large signal model in the embodiment of the present invention mainly includes a leakage model, that is, a nonlinear Ids model. The method for establishing the leakage model Ids taking into account the influence of ambient temperature is as follows: Figure 1 Optionally, the GaN-HEMT device in some embodiments of the present invention is a 4×100 μm GaN-HEMT device.

[0058] Among them, the pulse current-voltage test of GaN-HEMT devices in high and low temperature environments includes:

[0059] The ambient temperature of the GaN-HEMT device is set to different temperatures within a preset temperature range;

[0060] At any temperature, the GaN-HEMT device is subjected to a pulse current-voltage test to obtain current-voltage data.

[0061] Optionally, the preset temperature range includes 25°C-175°C, and different temperatures within the preset temperature range include 25°C, 50°C, 75°C, 100°C, 125°C, 150°C and 175°C, that is, the GaN-HEMT device is subjected to a pulse current-voltage test at ambient temperatures of 25°C, 50°C, 75°C, 100°C, 125°C, 150°C and 175°C to obtain current-voltage data. Of course, the present invention is not limited thereto, and in other embodiments, the preset temperature range and the values ​​of different temperatures may be adjusted according to actual conditions.

[0062] Optionally, when performing a pulse current-voltage test, the pulse width ranges from 200ns to 300ns, the period ranges from 200μm to 300μm, and the duty cycle ranges from 0.1% to 0.2%. Further, the pulse width can be 200ns, the period can be 200μm, and the duty cycle can be 0.1%.

[0063] It should be noted that short pulses and low duty cycles can ensure that the GaN-HEMT device is only affected by the ambient temperature and is basically not affected by the self-heating effect. In addition, the static bias point needs to be set to (0, 0) to ensure that the feeding mode of the gate and drain of the GaN-HEMT device is a pulse mode.

[0064] S102: Use the improved drain current formula to build a leakage model of the GaN-HEMT device, where the improved drain current formula includes parameters related to the ambient temperature;

[0065] In the embodiment of the present invention, the traditional drain current formula, namely the Tajima current formula, is improved. The traditional drain current formula is: ds =F g *F d *G md *i dss ;

[0066] in,

[0067] V p =V p0 +V φ +P*V ds ;

[0068] G md =1+βgmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm ))).

[0069] Considering the ambient temperature T j In some embodiments of the present invention, i dssth to i dss The Tajima current formula is improved by replacing it. Its physical meaning is similar to the concept of saturated leakage current. The expression is: I ds =F g *F d *G md *i dssth ;

[0070]

[0071] That is, in some embodiments of the present invention, the improved drain current formula is:

[0072] I ds =F g *F d *G md *i dssth ;

[0073] in,

[0074] V p =V p0 +V φ +P*V ds ;

[0075] G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm )));

[0076]

[0077] T j It is a parameter related to the ambient temperature.

[0078] Considering the influence of the ambient temperature Tj on the device, in some other embodiments of the present invention, V dspth V dspReplace to improve the Tajima current formula, which means taking into account the influence of ambient temperature on the inflection point position, which is mainly related to the "knee voltage", the expression is:

[0079]

[0080]

[0081] That is, in some embodiments of the present invention, the improved drain current formula is:

[0082] I ds =F g *F d *G md *i dss ;

[0083] in,

[0084] V p =V p0 +V φ +P*V ds ;

[0085] G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm )));

[0086] T j It is a parameter related to the ambient temperature.

[0087] Considering the ambient temperature T j In some embodiments of the present invention, W is used th The Tajima current formula is improved by replacing W. W mainly determines the influence of Vgs. Considering the influence of Vgs at different ambient temperatures, its expression is:

[0088]

[0089] W th =w0+w1*T j ;

[0090] That is, in some other embodiments of the present invention, the improved drain current formula is:

[0091] I ds =F g *Fd *G md *i dss ;

[0092] in,

[0093] V p =V p0 +V φ +P*V ds ; W th =w0+w1*T j ; G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm )));

[0094] T j It is a parameter related to the ambient temperature.

[0095] In some other embodiments of the present invention, the ambient temperature T j i dssth 、V dspth and W th All are replaced into Tajima current formula Ids. The improved drain current formula is:

[0096] I ds =F g *F d *G md *i dssth ;

[0097] in,

[0098] V p =V p0 +V φ +P*V ds ; W th =w0+w1*T j ;

[0099] G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm )));

[0100]

[0101] T j It is a parameter related to the ambient temperature.

[0102] In addition, the leakage model of GaN-HEMT devices is constructed using the improved drain current formula, including:

[0103] The improved drain current formula is written into the second port formula of the symbol definition device (SDD) in Agilent's RF integrated circuit design software ADS, so as to build a leakage model of the GaN-HEMT device using the symbol definition device in Agilent's RF integrated circuit design software;

[0104] The SDD device includes three ports, the first port is the input port of the gate voltage, the second port is the source-drain channel port, and the third port is the input port of the ambient temperature.

[0105] In some specific embodiments, the following can be constructed in ADS: Figure 3 The topology shown in the figure uses the symbolic definition device (SDD) in ADS to build the leakage model of the GaN-HEMT device. For example, a three-port SDD device is used, where the first port 1 is the input port of the gate voltage (Vgs), the second port 2 is the source and drain channel port, and the third port 3 is the ambient temperature T j Since the second port 2 represents the source-drain channel, the ambient temperature T j The drain current formula Ids that affects the drain current, that is, the improved drain current formula, is represented at the second port 2, so that simulation analysis can be performed through the symbol definition device (SDD) in ADS.

[0106] S103: Fitting the current-voltage data at different temperatures with the leakage model to determine the parameters of the leakage model.

[0107] In some specific embodiments, the current-voltage data at different temperatures can be fitted with the leakage model in Agilent RF integrated circuit design software ADS to determine the parameters of the leakage model. Of course, the present invention is not limited to this, and in other embodiments, other software can also be used for modeling and fitting.

[0108] Among them, the current-voltage data at different temperatures are fitted with the leakage model, and the parameters of the leakage model are determined including:

[0109] Fit the current-voltage data at room temperature to the leakage model to determine the temperature-independent parameters in the leakage model;

[0110] The current-voltage data at other temperatures are fitted to the leakage model to determine the temperature-related parameters in the leakage model.

[0111] For example, the current-voltage data at an ambient temperature of 25°C is fitted to the leakage model to determine the temperature-independent parameters in the leakage model, and the current-voltage data at ambient temperatures of 50°C, 75°C, 100°C, 125°C, 150°C, and 175°C are fitted to the leakage model to determine the temperature-dependent parameters in the leakage model. In some embodiments, the temperature-independent parameters include M, Vp0, Vphi, a, b, m, p, βgmd, αgmd, Vdm, and Vgm, etc., and the temperature-dependent parameters include idss0, idss1, idss2, idss3, vdspth0, vdspth1, vdspth2, vdspth3, wth0, and wth1, etc.

[0112] It should be noted that after the parameters of the leakage model are determined, the leakage model can be determined, and the large signal model of the GaN-HEMT device can be determined. After the large signal model considering the ambient temperature in the embodiment of the present invention is used for joint simulation with the measured data, as shown in FIG. Figures 4 to 10 As shown, there are comparison diagrams of model simulation data and measured data at 25℃, 50℃, 75℃, 100℃, 125℃, 150℃ and 175℃ respectively. It can be seen that the large signal model considering the ambient temperature can better predict the output characteristic curve of the device at different temperatures.

[0113] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other. The above description of the disclosed embodiments enables professionals and technicians in this field to implement or use the present invention. Various modifications to these embodiments will be obvious to professionals and technicians in this field, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown in this article, but will comply with the widest range consistent with the principles and novel features disclosed herein.

Claims

1. A modeling method for a large signal model of a GaN-HEMT device, characterized in that: include: Conduct pulse current-voltage tests on GaN-HEMT devices in high and low temperature environments to obtain current-voltage data at different temperatures; The improved drain current formula is used to build a leakage model of the GaN-HEMT device, wherein the large signal model includes the leakage model, and the improved drain current formula includes parameters related to the ambient temperature; Fitting the current-voltage data at different temperatures with the leakage model to determine the parameters of the leakage model; The leakage model of GaN-HEMT device is constructed by using the improved drain current formula, including: Write the improved drain current formula into the second port formula of the symbol definition device in the Agilent RFIC design software to build a leakage model of the GaN-HEMT device using the symbol definition device in the Agilent RFIC design software; The symbol definition device includes three ports, the first port is the input port of the gate voltage, the second port is the source-drain channel port, and the third port is the input port of the ambient temperature; The improved drain current formula is: ds =F g *F d *G md *i dss ; in, V p =V p0 +V φ +P*V ds ; W th =w0+w1*T j ;G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm ))); T j is a parameter related to the ambient temperature; Or, the improved drain current formula is: I ds =F g *F d *G md *i dssth ; in, V p =V p0 +V φ +P*V ds ; G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm ))); T j is a parameter related to the ambient temperature; Or, the improved drain current formula is: I ds =F g *F d *G md *i dss ; in, V p =V p0 +V φ +P*V ds ; G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm ))); T j is a parameter related to the ambient temperature; Or, the improved drain current formula is: I ds =F g *F d *G md *i dssth ; in, V p =V p0 +V φ +P*V ds ; W th =w0+w1*T j ; G md =1+β gmd *(V ds -V dm )*(1+tanh(α gmd *(V gs -V gm ))); T j It is a parameter related to the ambient temperature.

2. The method according to claim 1, characterized in that Pulse current-voltage testing of GaN-HEMT devices in high and low temperature environments includes: Setting the ambient temperature of the GaN-HEMT device to different temperatures within a preset temperature range; At any temperature, a pulse current-voltage test is performed on the GaN-HEMT device to obtain current-voltage data.

3. The method according to claim 2, characterized in that The preset temperature range includes 25°C-175°C, and different temperatures within the preset temperature range include 25°C, 50°C, 75°C, 100°C, 125°C, 150°C and 175°C.

4. The method according to claim 2, characterized in that: When performing a pulse current-voltage test, the pulse width ranges from 200ns to 300ns, the period ranges from 200μm to 300μm, and the duty cycle ranges from 0.1% to 0.2%.

5. The method according to claim 1, characterized in that Fitting the current-voltage data at different temperatures with the leakage model to determine the parameters of the leakage model includes: Fitting the current-voltage data at room temperature with the leakage model to determine parameters in the leakage model that are independent of temperature; The current-voltage data at other temperatures are fitted to the leakage model to determine the temperature-related parameters in the leakage model.

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