Investigation on the accuracy of the junction temperature determined by the VCE(T) method under different load pulse durations in power cycling test

When compared to temperature distributions in an actual application, thermal cycling is not a complete representation of the thermal gradients found in functional electronics under power-on condition. This discrepancy is particularly severe in power electronics and it distorts the thermo-mechanical stresses experienced at the joints and interfaces of power devices. Accelerated stress tests for power electronics are therefore better conducted with accelerated power cycling experiments rather than with accelerated thermal cycling, because the power cycles simulate more closely accelerated versions of an application cycle where the junction temperature of the die rises and falls as the power is turned off and on. However, developing a power cycling test setup can be comparatively more challenging than temperature cycling test setup, because of the complex triggering circuitry and logic needed for rapid power cycling, power circuitry needed to supply the large wattage safely to the devices under test, thermal cooling system to remove the high amount of heat generated, and software/hardware to control the test setup to maintain the right operational parameters. In this study, a test setup has been developed to power cycle IGBT and bipolar semiconductor devices for accelerated durability tests. The test setup is described and the role of each hardware and software component in the test setup is elaborated. Sample test results are presented, to illustrate the capabilities of the test setup. This work adds to the state of the art of power cycling experiments and improves our understanding of ways to develop stable power cycling test setups for various kinds of applications.

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Effect of load sequence interaction on bond-wire lifetime due to power cycling

Scientific Reports ◽

10.1038/s41598-021-84976-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Zoubir Khatir ◽

Son-Ha Tran ◽

Ali Ibrahim ◽

Richard Lallemand ◽

Nicolas Degrenne

Keyword(s):

High Stress ◽

Bipolar Transistors ◽

Junction Temperature ◽

Experimental Investigations ◽

Power Cycling ◽

Power Modules ◽

Bond Wire ◽

Load Sequence ◽

The Difference ◽

Heating Duration

AbstractExperimental investigations on the effects of load sequence on degradations of bond-wire contacts of Insulated Gate Bipolar Transistors power modules are reported in this paper. Both the junction temperature swing ($$\Delta T_{j}$$ Δ T j ) and the heating duration ($$t_{ON}$$ t ON ) are investigated. First, power cycling tests with single conditions (in $$\Delta T_{j}$$ Δ T j and $$t_{ON}$$ t ON ), are performed in order to serve as test references. Then, combined power cycling tests with two-level stress conditions have been done sequentially. These tests are carried-out in the two sequences: low stress/high stress (LH) and high stress/low stress (HL) for both $$\Delta T_{j}$$ Δ T j and $$t_{ON}$$ t ON . The tests conducted show that a sequencing in $$\Delta T_{j}$$ Δ T j regardless of the direction “high-low” or “low–high” leads to an acceleration of degradations and so, to shorter lifetimes. This is more pronounced when the difference between the stress levels is large. With regard to the heating duration ($$t_{ON}$$ t ON ), the effect seems insignificant. However, it is necessary to confirm the effect of this last parameter by additional tests.

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Low-Temperature Joining Technique as Interconnection Technology for Power Electronics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.324.437 ◽

2011 ◽

Vol 324 ◽

pp. 437-440

Author(s):

Raed Amro

Keyword(s):

Low Temperature ◽

Power Electronics ◽

Life Time ◽

Junction Temperature ◽

Limiting Factors ◽

Power Devices ◽

Packaging Technology ◽

Power Cycling ◽

Power Modules ◽

Bond Wires

There is a demand for higher junction temperatures in power devices, but the existing packaging technology is limiting the power cycling capability if the junction temperature is increased. Limiting factors are solder interconnections and bond wires. With Replacing the chip-substrate soldering by low temperature joining technique, the power cycling capability of power modules can be increased widely. Replacing also the bond wires and using a double-sided low temperature joining technique, a further significant increase in the life-time of power devices is achieved.

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