COMPARISON OF DIFFERENT DEVICE CONCEPTS TO INCREASE THE OPERATING VOLTAGE OF A TRENCH ISOLATED SOI TECHNOLOGY TO ABOVE 900V

For gate driver ICs in three phase power applications level shifters with more than 900V operating voltage are required. The extension of the voltage rating of an existing trench isolated SOI process was done with different device concepts: Serial stacking of lower voltage devices was evaluated as an alternative approach to conventional quasi-vertical and charge compensated lateral devices which need layout and material modifications. Based on sufficient 900V trench isolation the different device concepts were tested with diodes and transistors. For the usage as level shifters the focus was to achieve the required breakdown voltages with minimum area.