高压IGBT宽安全工作区设计

Design of High Voltage IGBT with Wide SOA

基于现有工艺平台开发了一款具有宽安全工作区的高压IGBT芯片。该芯片元胞采用场截止结构、载流子增强技术结合背面激光退火工艺降低器件饱和电压,通过优化载流子存储层的掺杂分布,结合背面透明集电极的增益优化,降低器件雪崩风险,提高器件的安全工作区。经流片测试结果显示饱和电压2.6 V,芯片在125°C温度下可实现5倍以上额定电流安全关断,短路电流可在30μs内安全关断,具有宽安全工作区水平,实现饱和电压、关断损耗和安全工作区的折衷。

A high voltage insulator gate bipolar transistor(IGBT)with wide safe operating area(SOA)was designed based on the existing technology platform.The saturation voltage was decreased by using the field-stop structure and the carrier enhancement technology combined with back laser annealing process.The avalanche risk of devices was reduced and the safe operating area of the device was improved by optimizing the concentration of the carrier enhancement layer and the gain optimization of transparent collector on the back.The test results show that the saturation voltage is 2.6 V,the chip can be safely turned off more than 5 times of the rated current at 125°C,and the short-circuit current can be safely turned off within 30μs,which has a wide SOA.The design achieves a compromise between the saturation voltage,the turn-off loss and the SOA.