Date: 12/10/2011

245GHz/450GHz SiGe:C transistors developed for automotive radars

Semiconductor and nanotechnology researcher Imec realized a fT/fMAX 245GHz/450GHz SiGe:C heterojunction bipolar transistor (HBT) device, which are used for generating close to terahertz frequency pulses in automotive radars. These HBT devices also pave the way to silicon-based millimeter wave circuits penetrating the so-called THz gap, enabling enhanced imaging systems for security, medical and scientific applications, says imec.

The key features of these devices include:

Based on fully self-aligned architecture by self-alignment of the emitter, base and collector region, and implement an optimized collector doping profile.
Compared to III-V HBT devices, SiGe:C HBTs combine high-density and low-cost integration, making them suitable for consumer applications.
Peak fMAX values above 450GHz are obtained on devices with a high early voltage, a BVCEO of 1.7V and a sharp transition from the saturation to the active region in the IC-VCE output curve.