Patent · US Expired

Insulated gate semiconductor device

US6342709B1 · kind B1 · utility

70Cited by
2References
20Claims
0Family size

Assignees

Inventors

Key dates

Filing dateAug 11, 1998
Grant dateJan 29, 2002
Priority date
Expiry dateAug 11, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D64/516

Abstract

In a semiconductor device having a trench type insulated gate structure, in the case where a drift layer 2 of an n− conduction type has a high carrier density, when a high voltage is applied between a drain and a source in such a manner that a channel is not formed, the electric field strength of an insulator layer 9 below the trench type insulated gate is increased, thus causing breakdown. The withstand voltage of the semiconductor device is limited by the breakdown of the insulator layer 9, and it is difficult to realize high withstand voltage.In the characteristic of the present invention, a field relaxation semiconductor region 1 of a conduction type opposite to the conduction type of the drift layer 2 is formed within the drift layer 2 below the insulator layer 9 in the trench of the trench type insulated gate semiconductor device. Also, the thickness of a bottom portion of the insulator layer 9 provided in the trench of the trench type insulated gate semiconductor device is made significantly greater than the thickness of a lateral portion thereof.

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