Patent · US Expired

Insulated gate bipolar transistor having high breakdown voltage in reverse blocking mode

US6448588B2 · kind B2 · utility

1Cited by
1References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 23, 2001
Grant dateSep 10, 2002
Priority date
Expiry dateFeb 23, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D62/60

Abstract

An insulated gate bipolar transistor having a high breakdown voltage in a reverse blocking mode and a method for fabricating the same are provided. The insulated gate bipolar transistor includes a relatively low-concentration lower buffer layer and a relatively high-concentration upper buffer layer. The low-concentration lower buffer layer contacts a semiconductor substrate having a high concentration of first conductivity type impurities used as a collector region, and the high-concentration upper buffer layer contacts a drift region of a second conductivity type. The conductivity type of the upper buffer layer is second conductivity type impurities, and the conductivity type of the lower buffer layer is substantially intrinsic, or first conductivity type impurities, or second conductivity type impurities. According to the present invention, due to the high-concentration upper buffer layer, the thickness of the drift region can be reduced, and during a forward continuity, a switching speed can be improved. Simultaneously, due the low-concentration lower buffer layer, the breakdown voltage of a device can be increased in a reverse blocking mode.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.