| 摘要 |
High frequency performance of (e.g., silicon) bipolar devices is improved by reducing the extrinsic base resistance Rbx. An emitter, intrinsic base and collector are formed in a semiconductor body. An emitter contact has a region that overlaps a portion of an extrinsic base contact. A sidewall is formed in the extrinsic base contact proximate a lateral edge of the overlap region of the emitter contact. The sidewall is amorphized during or after formation so that when the emitter contact and the extrinsic base contact are, e.g., silicided, some of the metal atoms forming the silicide penetrate into the sidewall so that part of the highly conductive silicided extrinsic base contact extends under the edge of the overlap region of the emitter contact closer to the intrinsic base, thereby reducing Rbx. Smaller Rbx provides transistors with higher fMAX. |
