In this study, degradation phenomena due to gate bias stress at elevated temperature for the reliability test of punch-through IGBTs, which are widely used in DC circuit systems for automotive applications, were investigated. For the reliability tests of various temperatures, 4000 times temperature cycle stress was applied in IGBTs between −40°C and 200°C to accelerate the degradation process using the wide range temperature. And the delamination of the passivation layer and the metal layer in IGBTs was observed using the scan acoustic microscopy. In addition, the positive bias stress with 48 V at elevated temperature of 150°C for 60 min was applied to the gate, the threshold voltage increased up to 6.07 V due to charge trapping at gate oxide. We also compared the recovery of the devices, but the IGBTs that stressed with high DC field and elevated temperature slowed down the recovery process after 24 hours without reverse voltage. This work was focused to find the device recovery considering real conditions. Therefore, the various temperature stress and high electric field stress are important in the reliability test for IGBTs, it was reported the IGBT degradation process and failure symptoms using the accelerated and various reliability tests.

中文翻译：

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不同温度环境下高栅极电压导致IGBT加速退化

在这项研究中，对广泛用于汽车应用的直流电路系统的穿通 IGBT 的可靠性测试在高温下由于栅极偏置应力引起的退化现象进行了研究。对于各种温度的可靠性测试，在-40°C至200°C之间的IGBT中施加4000次温度循环应力，以利用宽温度范围加速退化过程。并且使用扫描声学显微镜观察了IGBT中钝化层和金属层的分层。此外，在 150°C 的高温下对栅极施加 48 V 的正偏置应力 60 分钟，由于栅极氧化物处的电荷俘获，阈值电压增加到 6.07 V。我们还比较了设备的恢复情况，但承受高直流场和高温压力的 IGBT 在 24 小时没有反向电压后会减慢恢复过程。这项工作的重点是找到考虑实际条件的设备恢复。因此，各种温度应力和高电场应力在IGBT的可靠性测试中很重要，使用加速和各种可靠性测试报道了IGBT的退化过程和故障症状。