Semiconductor device with increased breakdown voltage
US5495124A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 26, 1993 |
| Grant date | Feb 27, 1996 |
| Priority date | — |
| Expiry date | Oct 26, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/858
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A low concentration impurity region 6 of a second conductivity type is formed to cover lower portion of a high concentration impurity region 8 of the second conductivity type. Consequently, impurity concentration gradient between the high concentration impurity region 8 of the second conductivity type and the low concentration impurity layer 2 of a first conductivity type can be made moderate to relax the electric field, which leads to provision of higher breakdown voltage of the semiconductor device. Further, the depth of impurity diffusion of the low concentration impurity region 6 of the second conductivity type from the main surface of the low concentration impurity layer 2 of the first conductivity type is made at least three times the depth of impurity diffusion of the high concentration impurity region 8 of the second conductivity type from the main surface of the low concentration impurity layer 2 of the first conductivity type. Therefore, minimum dimensions necessary for suppressing the electric field can be set in the semiconductor device, and therefore the semiconductor device comes to have higher breakdown voltage efficiently while not preventing miniaturization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.