Method for testing influence of heavy ion irradiation on inverse piezoelectric effect of gallium nitride high-electron-mobility transistor

Abstract

The invention relates to a method for testing the influence of heavy ion irradiation on the inverse piezoelectric effect of a gallium nitride high-electron-mobility transistor. The method comprises the steps of test sample selection and grouping, heavy ion irradiation testing and inverse piezoelectric effect testing. Due to the influence of the special piezoelectric effect of the gallium nitride high-electron-mobility transistor, the inverse piezoelectric effect can be caused under high voltage, and the performance of the transistor is reduced. A gallium nitride high-electron-mobility transistor working in a radiation environment is irradiated by heavy ions, and defects are introduced into the transistor. Defects introduced by heavy ions may further influence the inverse piezoelectric effect of the transistor, so that the interaction of the two needs to be considered at the same time in a heavy ion irradiation environment. By establishing a test method, the influence of heavy ion irradiation on the inverse piezoelectric effect of the gallium nitride high-electron-mobility transistor is finally obtained.

Description

Technical Field

[0001] This invention relates to a test method for the effect of heavy ion irradiation on the inverse piezoelectric effect of gallium nitride high electron mobility transistors, belonging to the field of microelectronic device testing technology. Background Technology

[0002] Gallium nitride high electron mobility transistors (GaN HEMTs) have attracted much attention due to their radiation resistance, high voltage resistance, high temperature resistance, and high power characteristics. Compared with traditional Si-based devices, GaN HEMTs exhibit better radiation resistance, higher breakdown voltage, lower parasitic capacitance, higher switching frequency, and higher mobility. Without any artificial doping, GaN HEMTs can achieve an areal density of 10-1 at the AlGaN / GaN interface solely through the material's own polarization. 13 / cm 2 High-concentration two-dimensional electron gas (2-DEG) has become a key component in broadband communication satellites, phased array radars, and other equipment, playing an important role in aerospace and other fields.

[0003] Gallium nitride high electron mobility transistors (GaN HEMTs) theoretically offer significant advantages over Si-based devices. However, due to factors such as fabrication processes, operating environments, and usage conditions, reliability issues arise in practical applications. The inverse piezoelectric effect has always been a significant concern in GaN HEMT devices, influencing their electrical parameters and degrading their performance. GaN HEMT devices operating in heavy ion environments are simultaneously affected by heavy ion irradiation and the inverse piezoelectric effect, and their interaction leads to performance degradation.

[0004] Current research on the inverse piezoelectric effect of gallium nitride high electron mobility transistors (GaN HEMTs) is mostly focused on pure inverse piezoelectricity. Most studies on the effects of irradiation and electric fields only investigate the influence of applying a bias stress during irradiation on the device, without paying attention to the impact of heavy ion irradiation defects on inverse piezoelectricity.

[0005] This invention proposes an experimental method for the effect of heavy ion irradiation on the inverse piezoelectric effect of gallium nitride (GaN) high electron mobility transistors (HEMTs). Three methods were designed: sample selection and grouping, heavy ion irradiation testing, and inverse piezoelectric effect testing. These methods were used to obtain the impact of heavy ion irradiation on the inverse piezoelectric effect of GaN HEMT devices, providing support for the reliability assessment of device radiation environment. Summary of the Invention

[0006] The purpose of this invention is to provide an experimental method for studying the effect of heavy ion irradiation on the inverse piezoelectric effect of gallium nitride (GaN) high electron mobility transistors (HETTs). This method comprises sample selection and grouping, heavy ion irradiation experiments, and inverse piezoelectric effect experiments. Due to its unique piezoelectric effect, GaN HETTs exhibit an inverse piezoelectric effect at high voltages, leading to a decline in transistor performance. When GaN HETTs operating in a radiation environment are irradiated with heavy ions, defects are introduced into the transistor. These defects introduced by heavy ions may further affect the inverse piezoelectric effect, necessitating the simultaneous consideration of the interaction between the two in heavy ion irradiation environments. By establishing an experimental method, the influence of heavy ion irradiation on the inverse piezoelectric effect of GaN HETTs can be obtained.

[0007] The present invention discloses an experimental method for the effect of heavy ion irradiation on the inverse piezoelectric effect of gallium nitride high electron mobility transistors. This method comprises sample selection and grouping, heavy ion irradiation experiments, and inverse piezoelectric effect experiments. The specific operation is carried out according to the following steps:

[0008] Sample selection and grouping:

[0009] a. Select gallium nitride high electron mobility transistors (GaN transistors) of the same manufacturer and model for cap removal treatment, and test the transfer characteristic curves of the cap-removed devices at room temperature. DS -V GS Output characteristic curve I DS -V DS Schottky characteristic curve I GS -V GS The threshold voltage V of the test device th On-resistance R DS(on) Gate resistance R G Drain leakage current I DSS Gate leakage current I GSS Output capacitor C iss Input capacitor C oss and reverse transfer capacitor C rss Parameters; Select devices with similar initial values ​​from qualified devices as test samples and number them according to the numbering rules. Divide the numbered test samples into a pre-irradiation group and a control group. The pre-irradiation group undergoes heavy ion irradiation test before the inverse piezoelectric test. There are no less than 3 test samples under each test condition.

[0010] Heavy ion irradiation experiment:

[0011] b. Conduct heavy ion irradiation experiments on the test samples from the pre-irradiation group in step a, and set the gate-source voltage V. GS =0V, by applying stepped stress, the drain-source voltage V is changed. DSFind the threshold voltage at which the test sample undergoes single-particle burn-off under irradiation, and denote this voltage as B; set the gate-source voltage V. GS =0V, drain-source voltage V DS Below B; additionally set up a zero-bias irradiation group: V GS =0V, V DS =0V, total injection volume is 1E7 ions / cm 2 Or 0.8×C; During the irradiation test, an online testing method is used to monitor the gate current and leakage current of the test sample. After the test, the final value of the test sample is tested, and the test parameters are consistent with the initial value test.

[0012] c. Inverse piezoelectric effect test:

[0013] Inverse piezoelectric effect tests were conducted under the same conditions on the pre-irradiated group and the control group. The test samples from step b were subjected to inverse piezoelectric tests, including the gate-source voltage V. GS =0V, drain-source voltage V DS =0.5B and V DS Two groups of pre-irradiated test samples with a voltage of 0V were prepared. Then, the test samples of the control group in step a were subjected to reverse voltage tests under the same conditions as the pre-irradiated group. In the reverse piezoelectric test, stress was applied in a stepped stress manner. Before the reverse piezoelectric test, the initial value tests were performed on the test samples of the pre-irradiated group and the control group in step a, respectively. After the reverse piezoelectric test, the final value was tested. The parameters of the final value test were kept consistent with the initial value test. The parameter changes before and after the reverse piezoelectric stress in the pre-irradiated group and the control group were extracted to obtain the effect of heavy ion irradiation on the reverse piezoelectric effect of GaN HEMT devices.

[0014] This invention discloses an experimental method for investigating the effect of heavy-ion irradiation on the inverse piezoelectric effect of gallium nitride high electron mobility transistors. In this method, because the plastic-encapsulated devices are too thick, heavy ions cannot reach the device surface, necessitating a cap-opening process. However, operational errors during the cap-opening process can lead to differences in the electrical parameters of devices with similar initial values. By screening the cap-opened devices, those with similar and normal parameters after cap-opening can be selected as backup devices for testing. Finally, through heavy-ion irradiation and inverse piezoelectric experiments, the changes in parameters can be obtained, allowing for analysis of the impact of heavy-ion irradiation on the inverse piezoelectric effect.

[0015] The present invention provides an experimental method for studying the effect of heavy ion irradiation on the inverse piezoelectric effect of gallium nitride high electron mobility transistors. The beneficial effects of this method are as follows:

[0016] This study avoids the impact of device cap opening on experimental results; it obtains the effect of heavy ion irradiation on device characteristics under different drain voltage bias conditions without single-event burn-in; and it reveals the mechanism of the influence of defects introduced by heavy ion irradiation on the inverse piezoelectric effect through defect testing methods. This provides support for the reliability assessment of device radiation environment.

[0017] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, the following are the embodiments of this application and are described in detail with reference to the accompanying drawings. Attached Figure Description

[0018] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0019] Example

[0020] This invention discloses an experimental method for investigating the effect of heavy ion irradiation on the inverse piezoelectric effect of gallium nitride high electron mobility transistors. The method comprises sample screening, heavy ion irradiation testing, and testing the inverse piezoelectric effect. The flowchart of the experimental method is shown below. Figure 1 As shown: The specific operation is carried out according to the following steps:

[0021] Sample selection and grouping:

[0022] a. Select gallium nitride high electron mobility transistors (GaN transistors) of the same manufacturer and model for cap removal treatment, and test the transfer characteristic curves of the cap-removed devices at room temperature. DS -V GS Output characteristic curve I DS -V DS Schottky characteristic curve I GS -V GS The threshold voltage V of the test device th On-resistance R DS(on) Gate resistance R G Drain leakage current I DSS Gate leakage current I GSS Output capacitor C iss Input capacitor C oss and reverse transfer capacitor C rssParameters; To better analyze the mechanism of heavy ion irradiation defects on the inverse piezoelectric effect, it is recommended to conduct defect charge testing. It is important to note that due to the special nature of power devices, the test parameters should include high-voltage characteristic parameters. Select 15 devices with similar initial values ​​from qualified devices as test samples and number them according to the numbering rules. Divide the numbered test samples into a pre-irradiation group and a control group. The pre-irradiation group undergoes heavy ion irradiation testing before the inverse piezoelectric test, while the control group does not. Test samples 1-2 serve as preliminary samples for the pre-irradiation group, test samples 3-5 are 0.5B bias irradiation samples for the pre-irradiation group, test samples 6-8 are 0 bias irradiation samples for the pre-irradiation group, samples 9-11 are test samples for the control group, and samples 12-15 are reserve samples. The total number of samples can be determined according to the actual situation. To ensure the statistical validity of the data, at least 3 test samples should be used under each test condition.

[0023] Heavy ion irradiation experiment:

[0024] b. Conduct heavy ion irradiation experiments on the test samples of the pre-irradiation group from step a. First, perform a preliminary test on samples 1-2#, and set the gate-source voltage V. GS =0V, by applying stepped stress, the drain-source voltage V is changed. DS Find the threshold voltage at which the test sample undergoes single-particle burn-off under irradiation, and denote this voltage as B; set the gate-source voltage V. GS =0V, drain-source voltage V DS If the answer is lower than B, such as choosing V DS =0.5×B, use samples 3-5# to determine the total flux that causes single-particle burn-off under these conditions; if the total flux that causes burn-off is greater than 1E7 ions / cm 2 Then select 1E7 ions / cm 2 The total irradiation flux is 0.8 times the total flux C at which burnout occurs, which is selected as the total flux in the test. Additionally, a zero-bias irradiation group is set up to conduct irradiation tests on samples 6-8#: V GS =0V, V DS =0V, total injection volume is 1E7 ions / cm 2 Or 0.8×C. If the test sample burns out, the irradiation should be stopped early and the test sample replaced. During the irradiation test, the gate current and leakage current of the device should be monitored by online testing. After the test, the final value of the test sample should be tested, and the test parameters should be consistent with the initial value test.

[0025] Inverse piezoelectric effect test:

[0026] c. Conduct inverse piezoelectric effect tests under the same conditions on the pre-irradiated group and the control group from step a. First, conduct inverse piezoelectric tests on the test samples that did not burn out in step b, including the gate-source voltage V.GS =0V, drain-source voltage V DS =0.5B and V DS Two groups of pre-irradiated test samples with a voltage of 0V were used. Then, the 9-11# devices of the control group in step a were subjected to inverse piezoelectric tests under the same conditions as the pre-irradiated groups. In the inverse piezoelectric test, stress was applied using a stepped stress method, and the stepped stress was set to: V GS =0V, V DS =50-300V, step=50V, time=100s. Before the inverse piezoelectric test, the initial values ​​of the pre-irradiated group and the control group devices in step a are tested respectively. After the inverse piezoelectric test, the final values ​​are tested. The parameters of the final value test are consistent with those of the initial value test. The parameter changes before and after the inverse piezoelectric stress of the pre-irradiated group and the control group are extracted to obtain the effect of heavy ion irradiation on the inverse piezoelectric effect of gallium nitride high electron mobility transistor.

Claims

1. A test method for the effect of heavy ion irradiation on the inverse piezoelectric effect of gallium nitride high electron mobility transistors, characterized in that... This method consists of sample selection and grouping, heavy ion irradiation testing, and inverse piezoelectric effect testing. The specific operation is carried out according to the following steps: Sample selection and grouping: a. Select gallium nitride high electron mobility transistors (GaN transistors) of the same manufacturer and model for cap removal treatment, and test the transfer characteristic curves of the cap-removed devices at room temperature. DS -V GS Output characteristic curve I DS -V DS Schottky characteristic curve I GS -V GS The threshold voltage V of the test device th On-resistance R DS(on) Gate resistance R G Drain leakage current I DSS Gate leakage current I GSS Output capacitor C iss Input capacitor C oss and reverse transfer capacitor C rss Parameters; Select devices with similar initial values ​​from qualified devices as test samples and number them according to the numbering rules. Divide the numbered test samples into a pre-irradiation group and a control group. The pre-irradiation group undergoes heavy ion irradiation test before the inverse piezoelectric test. There are no less than 3 test samples under each test condition. Heavy ion irradiation experiment: b. Conduct heavy ion irradiation experiments on the test samples from the pre-irradiation group in step a, and set the gate-source voltage V. GS =0V, by applying stepped stress, the drain-source voltage V is changed. DS Find the threshold voltage at which the test sample undergoes single-particle burn-off under irradiation, and denote this voltage as B; set the gate-source voltage V. GS =0V, drain-source voltage V DS Below B; additionally set up a zero-bias irradiation group: V GS =0V,V DS =0V, total injection volume is 1E7 ions / cm 2 Or 0.8 × C; During the irradiation test, an online testing method was used to monitor the gate current and leakage current of the test sample. After the test, the final values ​​of the test sample were tested, and the test parameters were kept consistent with the initial values. Inverse piezoelectric effect test: c. Conduct inverse piezoelectric effect tests under the same conditions on the pre-irradiated group and the control group. Perform inverse piezoelectric tests on the test samples from step b, including the gate-source voltage V. GS =0V, drain-source voltage V DS =0.5B and V DS Two groups of pre-irradiated test samples were prepared at 0V. Then, the test samples of the control group in step a were subjected to reverse voltage tests under the same conditions as the pre-irradiated group. In the reverse piezoelectric test, stress was applied in a stepped stress manner. Before the reverse piezoelectric test, the initial value tests were performed on the test samples of the pre-irradiated group and the control group in step a, respectively. After the reverse piezoelectric test, the final value was tested. The parameters of the final value test were consistent with those of the initial value test. The parameter changes before and after the reverse piezoelectric stress in the pre-irradiated group and the control group were extracted to obtain the effect of heavy ion irradiation on the reverse piezoelectric effect of GaN HEMT devices.

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