Sub-2Opsec ECL Circuits with SOGHz fmax Self-aligned SiGe HBTs

This paper describes a high fmax self-aligned SiGe heterojunction bipolar transistor (HBT) technology which is based on the self-aligned selective epitaxial growth technology including Ge graded profile and link-base engineering using a BSG sidewall structure. The HBT has a super self-aligned - Selectively grown SiGe Base (SSSB) structure. Base prolile design and 2-step annealing technique have realized fT of SlGHz and low sheet resistance at the link-base region, and furthermore have accomplished fmax of as high as 5OGIIz. ECL circuits of l9psec gate delay have been achieved by using this SiGe HBT technology.