High performance bipolar transistor
US6506659B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 2001 |
| Grant date | Jan 14, 2003 |
| Priority date | — |
| Expiry date | Mar 17, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D10/891
Abstract
In one disclosed embodiment, a collector is deposited and a base is grown on the collector, for example, by epitaxially depositing either silicon or silicon-germanium. An emitter is fabricated on the base followed by implant doping an extrinsic base region. For example, the extrinsic base region can be implant doped using boron. The extrinsic base region doping diffuses out during subsequent thermal processing steps in chip fabrication, creating an out diffusion region in the device, which can adversely affect various operating characteristics, such as parasitic capacitance and linearity. The out diffusion is controlled by counter doping the out diffusion region. For example, the counter doped region can be implant doped using arsenic or phosphorous. Also, for example, the counter doped region can be formed using tilt implanting or, alternatively, by implant doping the counter doped region and forming a spacer on the base prior to implanting the extrinsic base region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.