Semiconductor switch devices having a region with three distinct zones and their manufacture
US6355971B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1999 |
| Grant date | Mar 12, 2002 |
| Priority date | — |
| Expiry date | Feb 25, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D10/441
Abstract
In a semiconductor switch device such as an NPN transistor (T) or a power switching diode (D), a multiple-zone first region (1) of one conductivity type forms a switchable p-n junction (12) with a second region (2) of opposite conductivity type. In accordance with the invention, this first region (1) includes three distinct zones, namely a low-doped zone (23), a high-doped zone (25), and an intermediate additional zone (24). The low-doped zone (23) is provided by a semiconductor body portion (11) having a substantially uniform p-type doping concentration (P−) and forms the p-n junction (12) with the second region (2). The distinct additional zone (24) is present between the low-doped zone (23) and the high-doped zone (25). The high-doped zone (25) which may form a contact zone has a doping concentration (P++) which is higher than that of the low-doped zone (23) and which decreases towards the low-doped zone (23). The distinct additional zone (24) has an additional doping concentration (P+) which is lower than the doping concentration (P++) of the high-doped zone (25) and which decreases towards the low-doped zone (23). This triple-zone formation for the first region (1) permi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.