Modular deep trench isolation scheme for 38 GHz self-aligned double polysilicon bipolar devices

A modulator CMOS-compatible isolation scheme which is based on a deep trench technology combined with LOCOS is presented. In contrast to already established schemes, trench formation is postponed until after the LOCOS process. Thus thermal cycling is minimized. The high-performance potential of this isolation technology is demonstrated via fabrication of self-aligned double polysilicon transistors featuring a maximum cutoff frequency of 38 GHz.<
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