Impact of Short-circuit events on Life- time Expectancy of SiC MOSFETs
Translated title
Impact of Short-circuit events on Lifetime Expectancy of SiC MOSFETs
Author
Martello, Giovanni
Term
4. semester
Education
Publication year
2024
Submitted on
2024-01-05
Pages
70
Abstract
Siliciumkarbid (SiC) MOSFET'er giver høj effektivitet og hurtig kobling, men i praksis lever deres levetid ofte ikke op til forventningerne og kan være kortere end for siliciumbaserede enheder, blandt andet på grund af variationer i produktionen og ikke fuldt forståede fejlmekanismer. Dette projekt undersøger, hvordan ikke-destruktive kortslutningshændelser påvirker levetidsforventningen for SiC MOSFET'er, med fokus på om enheder, der er stresset af kortslutninger med energi under den kritiske grænse, ældes hurtigere end intakte komponenter, men langsommere end synligt beskadigede komponenter. Levetiden vurderes med DC power cycling, den gængse metode til at evaluere slid under termisk og elektrisk belastning. Et AC power-cycling-udstyr er tilpasset til DC-drift ved udvikling af en dedikeret belastningsadapter, og enhederne er karakteriseret inden test. Tre batches forberedes og sammenlignes: ikke kortsluttede, kortsluttede med synlige skader og kortsluttede uden synlige skader. Rapporten gennemgår målinger og relevante parametre, forventede effekter af kortslutning samt testudstyr og procedurer. Detaljerede resultater og bølgeformer findes i den fulde afhandling; de indgår ikke i dette uddrag.
Silicon carbide (SiC) MOSFETs offer high efficiency and fast switching, yet in practice their lifetime often falls short of expectations and can be lower than that of silicon devices, partly due to manufacturing variability and not fully understood failure mechanisms. This project investigates how non-destructive short-circuit events influence the lifetime expectancy of SiC MOSFETs, asking whether devices stressed by short circuits with energy below the critical limit age faster than pristine parts but slower than visibly damaged parts. Lifetime is assessed by DC power cycling, the standard method to evaluate wear-out under thermal and electrical stress. An AC power-cycling setup was adapted for DC operation by developing a dedicated load adaptor, and devices were characterized before testing. Three batches were prepared and compared: not short-circuited, short-circuited with observable damage, and short-circuited without visible damage. The thesis outlines measurements and parameters of interest, expected short-circuit effects, and the test hardware and procedures. Detailed results and waveforms are presented in the full work; they are not included in this excerpt.
[This summary has been generated with the help of AI directly from the project (PDF)]
Documents