Modeling of large area trench IGBTs: The effect of birds-beak
IEEE Transactions on Electron Devices
Institute of Electrical and Electronics Engineers
MetadataShow full item record
Findlay, E., & Udrea, F. (2019). Modeling of large area trench IGBTs: The effect of birds-beak. IEEE Transactions on Electron Devices, 66 (6), 2686-2691. https://doi.org/10.1109/TED.2019.2911020
Three-dimensional modelling is becoming an increasingly prevalent technique to model more complex device structures. However, this alone is insufficient to accurately model large area devices. This study images the birds-beak in a commercial Insulated Gate Bipolar Transistor (IGBT) and highlights how this processing uncertainty, which impacts the channel properties, has a strong effect on the accuracy of TCAD simulations; resulting in the designer struggling to validate models and underappreciating the true behaviour of the device. It has been demonstrated that the birds-beak effect can be accounted for by a simple two-device model which allows for small-scale and large-scale device behaviours to be matched while limiting the computational effort for designers. The practical effects of birds-beaking on device performance has also been considered, and it has been shown that the variation in threshold voltage across the chip area results in a 32% reduction in short-circuit endurance time for the device. To overcome this, an alternative n+ emitter implantation is proposed, using a combination of arsenic and phosphorus, so that the device threshold is unaffected by the presence of birds-beaking and its variation during processing.
This work was supported in part by UK Innovate Project Number 102878. E. M. Findlay was funded by an EPSRC Doctoral Training Partnership scheme (grant RG75686).
Technology Strategy Board (102878)
External DOI: https://doi.org/10.1109/TED.2019.2911020
This record's URL: https://www.repository.cam.ac.uk/handle/1810/291737
All rights reserved