Method for testing through-current capability and service life of diode

Abstract

The invention relates to the technical field of integrated circuit testing, and particularly discloses a diode through-current capability and service life testing method which comprises the following steps: detecting whether a diode is good or not; applying forward current to the detected diode, and judging the breakdown current of the diode; selecting different current values based on the breakdown current, carrying out a current resistance test on the diode, and recording the failure time when the voltage is suddenly changed; analyzing the failure mode of the diode based on the failure time when the voltage is suddenly changed, confirming the reverse current test, and finding out the real failure time of the diode; and fitting the data of testing the real failure time under different current values to obtain a service life formula of the diode under different current values, and further calculating the service life of the diode under different current values. According to the method, the forward current is applied to the diode, the breakdown current is judged, different current values are selected based on the breakdown current, the real failure time of the diode is found out, data fitting is carried out, and therefore the service life of the diode under different currents is calculated.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuit testing, and in particular to a method for testing the current carrying capacity and life of a diode. Background Art

[0002] The maximum current capacity and lifespan of diodes in different integrated circuit processes are important parameters. However, existing industry testing methods do not yet exist to measure the current capacity and lifespan of diodes at different currents.

[0003] To address this issue, we developed a test method to evaluate the current-carrying capacity and lifespan of diodes at different currents. This method has been well-received and recognized by customers and is of great significance for evaluating the current-carrying capacity and lifespan of diodes at different currents.

[0004] Based on this technical background, the present invention proposes a method for testing the current carrying capacity and life of a diode. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention proposes a diode current carrying capacity and life testing method. By applying a forward current to the diode, its breakdown current is determined, and different current values ​​are selected based on the breakdown current, the diode is tested for current resistance and failure mode is analyzed to find the actual failure time of the diode. The data is then fitted to obtain the life formula of the diode under different currents, thereby calculating the life of the diode under different currents.

[0006] In order to achieve the above object, the present invention provides a method for testing the current carrying capacity and life of a diode, comprising:

[0007] Check the quality of diodes;

[0008] applying a forward current to the diode that has passed the test to determine its breakdown current;

[0009] Selecting different current values ​​based on the breakdown current, performing a current withstand test on the diode, and recording the failure time when the voltage suddenly changes;

[0010] Based on the failure time when the voltage suddenly changes, the failure mode of the diode is analyzed and confirmed by reverse current testing to find out the actual failure time of the diode;

[0011] The data of the actual failure time tested at different current values ​​are fitted to obtain the life formula of the diode at different currents, and then the life of the diode at different currents is calculated.

[0012] The technical effects of the present invention include:

[0013] The present invention proposes a diode current carrying capacity and life testing method. By applying a forward current to the diode, its breakdown current is determined. Based on the breakdown current, different current values ​​are selected to perform current withstand tests and failure mode analysis on the diode to find the actual failure time of the diode. The data is then fitted to obtain a formula for the diode life under different currents, thereby calculating the diode life under different currents.

[0014] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.

[0016] Figure 1 This is a flow chart of a diode current carrying capacity and life testing method proposed by the present invention.

[0017] Figure 2 This is a schematic diagram of detecting the quality of a diode in a specific embodiment of a diode current carrying capacity and life testing method proposed by the present invention.

[0018] Figure 3 This is a schematic diagram of determining the breakdown current through an IV curve in a specific embodiment of a diode current carrying capacity and life testing method proposed by the present invention.

[0019] Figure 4 This is a schematic diagram of analyzing and confirming the failure mode of a diode in a specific embodiment of a diode current carrying capacity and life testing method proposed by the present invention.

[0020] Figure 5 This is a schematic diagram of a 2.5VP diode life fitting curve in a specific embodiment of a diode current capacity and life testing method proposed by the present invention.

[0021] Figure 6 This is a schematic diagram of a 2.5V N-type diode life fitting curve in a specific embodiment of a diode current capacity and life testing method proposed by the present invention.

[0022] Figure 7 This is a schematic diagram of a 1.5VP diode life fitting curve in a specific embodiment of a diode current capacity and life testing method proposed by the present invention.

[0023] Figure 8This is a schematic diagram of a 1.5V N-type diode life fitting curve in a specific embodiment of a diode current capacity and life testing method proposed by the present invention. DETAILED DESCRIPTION

[0024] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0025] In the present invention, unless otherwise specified, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of a device in normal use, and "inner" and "outer" refer to positions relative to the device's outline. Furthermore, the terms "first, second, and third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Therefore, features defined as "first, second, and third" may explicitly or implicitly include one or more of such features. In the description of the present invention, "plurality" means two or more, unless otherwise explicitly and specifically defined.

[0026] The present invention provides a method for testing the current carrying capacity and life of a diode. Figure 1 As shown, including:

[0027] Check the quality of diodes;

[0028] Apply a forward current to the diode passing the test to determine its breakdown current;

[0029] Based on the breakdown current, different current values ​​are selected to test the current resistance of the diode and record the failure time when the voltage suddenly changes;

[0030] Based on the failure time when the voltage changes suddenly, the failure mode of the diode is analyzed and confirmed by reverse current test to find out the actual failure time of the diode;

[0031] The data of the actual failure time tested at different current values ​​are fitted to obtain the life formula of the diode at different currents, and then the life of the diode at different currents is calculated.

[0032] In the present invention, a forward current is applied to the diode to determine its breakdown current. Different current values ​​are selected based on the breakdown current, and the diode is subjected to a current withstand test and failure mode analysis to find the actual failure time of the diode. The data is then fitted to obtain a formula for the diode's life under different currents, thereby calculating the diode's life under different currents.

[0033] According to the present invention, detecting the quality of the diode under test includes:

[0034] Perform a reverse current sweep test on the diode. If the diode turns on normally under the set initial current and turn-on voltage, the diode is considered to have passed the test; otherwise, the diode is considered to have failed the test.

[0035] According to the present invention, applying a forward current to a diode passing through detection and determining its breakdown current includes:

[0036] Apply a forward current to the diode that has passed the test, gradually increase the scanning current to obtain the IV curve of the diode, and determine its breakdown current through the IV curve;

[0037] In the IV curve, the diode breakdown precedes the metal and / or via breakdown.

[0038] According to the present invention, selecting different current values ​​based on the breakdown current includes:

[0039] Different current values ​​are selected within the range of 0.7 to 0.9 times the breakdown current.

[0040] According to the present invention, analyzing the failure mode of the diode based on the failure time when the voltage suddenly changes includes:

[0041] Based on the failure time when the voltage suddenly changes, it is determined whether the voltage of the diode suddenly decreases or increases over time when the diode fails, and then the failure mode of the diode is determined.

[0042] Preferably, confirming the reverse current test of the diode includes:

[0043] Perform a reverse current sweep test on the diode to confirm the current value corresponding to the diode breakdown.

[0044] According to the present invention, the actual failure time of a diode is the time corresponding to when its current value does not change with its voltage value.

[0045] According to the present invention, the expression of the life formula is:

[0046] Y=AX -B ;

[0047] Where A and B are fitting coefficients, Y is current, and X is time.

[0048] According to the present invention, the breakdown current is used to measure the current carrying capacity of the diode.

[0049] According to the present invention, the diode is fabricated in a RFSOI process.

[0050] The present invention will be described in more detail below through specific examples.

[0051] Example 1

[0052] like Figure 1 As shown, this embodiment provides a method for testing the current carrying capacity and life of a diode, including:

[0053] Step 1: Check the quality of the diode before testing; reverse test the leakage current of the diode to check the initial quality of the device;

[0054] Step 2: Pass current through the diode device in the forward direction and test the breakdown current of the diode device by gradually increasing the current scan method;

[0055] Step 3: Determine the breakdown current of the diode device through the IV curve;

[0056] Step 4: Select different current values ​​within the range of 0.7 to 0.9 times the breakdown current Ibd and conduct a long-term current withstand test;

[0057] Step 5: Monitor the IV curve and confirm the original data of the diode device, and record the failure time when the voltage mutation is found;

[0058] Step 6: Analyze the diode failure mode and conduct reverse testing to confirm and find out the actual failure time of the diode;

[0059] Step 7: Use the failure time data of different current values ​​to fit and derive the life formula of the diode device under different currents; through the life formula, the life of the diode under different currents can be calculated.

[0060] The key steps in this embodiment are:

[0061] Step 1: If Figure 2 As shown, the device is confirmed to be good or bad; only after the previous confirmation can the subsequent tests be carried out normally;

[0062] Step 3: If Figure 3 As shown, the breakdown current of the diode device is determined, wherein the diode breakdown occurs before the metal and / or via breakdown;

[0063] Step 6: If Figure 4 As shown, the failure mode is confirmed and the actual failure time of the diode is found. Specifically, it is determined whether the voltage of the diode suddenly decreases or increases over time when the diode fails, and then the failure mode of the diode is determined. At the same time, a reverse current scan test is performed on the diode to confirm the current value corresponding to the diode breakdown.

[0064] In this embodiment, the life prediction data of the diode is shown in Table 1.

[0065] Table 1 Diode life prediction data

[0066]

[0067] In Table 1, the life fitting curves of 2.5VP diode, 2.5VN diode, 1.5VP diode and 1.5VP diode are as follows: Figure 5 、 Figure 6 、 Figure 7 and Figure 8 As shown, where R 2 is the fitted variance.

[0068] An embodiment of the present invention proposes a method for testing the current carrying capacity and life of a diode. By applying a forward current to the diode, its breakdown current is determined. Based on the breakdown current, different current values ​​are selected to perform a current withstand test and failure mode analysis on the diode to find the actual failure time of the diode. The data is then fitted to obtain a formula for the diode's life under different currents, thereby calculating the diode's life under different currents.

[0069] While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A diode current carrying capacity and life testing method, characterized in that: include: Check the quality of diodes; applying a forward current to the diode that has passed the test to determine its breakdown current; Selecting different current values ​​based on the breakdown current, performing a current withstand test on the diode, and recording the failure time when the voltage suddenly changes; Based on the failure time when the voltage suddenly changes, the failure mode of the diode is analyzed and confirmed by reverse current testing to find out the actual failure time of the diode; The data of the actual failure time tested at different current values ​​are fitted to obtain the life formula of the diode at different currents, and then the life of the diode at different currents is calculated.

2. The method according to claim 1, characterized in that Detecting the quality of the diode under test includes: A reverse current scanning test is performed on the diode. If the diode is normally turned on under the set initial current and turn-on voltage, the diode is considered to have passed the test; otherwise, the diode is considered to have failed the test.

3. The method according to claim 1, characterized in that Applying a forward current to the diode that has passed the test and determining its breakdown current includes: Applying a forward current to the diode that has passed the test, gradually increasing the scanning current to obtain an IV curve of the diode, and determining its breakdown current based on the IV curve; In the IV curve, the diode breakdown precedes the metal and / or via breakdown.

4. The method according to claim 1, wherein Selecting different current values ​​based on the breakdown current includes: Different current values ​​are selected within the range of 0.7 to 0.9 times of the breakdown current.

5. The method according to claim 1, wherein Analyzing the failure mode of the diode based on the failure time when the voltage suddenly changes includes: Based on the failure time when the voltage suddenly changes, it is determined whether the voltage of the diode suddenly decreases or increases over time when the diode fails, thereby determining the failure mode of the diode.

6. The method according to claim 1, characterized in that Confirmation of the reverse current test of the diode includes: Perform a reverse current scan test on the diode to confirm the current value corresponding to the breakdown of the diode.

7. The method according to claim 1, characterized in that The actual failure time of the diode is the time corresponding to the current value not changing with the voltage value.

8. The method according to claim 1, characterized in that The expression of the life formula is: Y=AX -B ; Where A and B are fitting coefficients, Y is current, and X is time.

9. The method according to claim 1, characterized in that The breakdown current is used to measure the current carrying capacity of the diode.

10. The method according to claim 1, characterized in that The diode is fabricated in RFSOI process.

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