Patent · US Expired

Method of making a trench capacitor for dram

US4859622A · kind A · utility

24Cited by
3References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 2, 1988
Grant dateAug 22, 1989
Priority date
Expiry dateAug 2, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D1/68

Abstract

Two or three trenches are formed in a silicon substrate, and a conductive layer is formed in the silicon substrate facing the trenches. An oxide film for insulation is formed on a surface of the conductive layer facing the trenches. The trenches are filled with polysilicon, and the conductive layer and the polysilicon constitute a capacitor through the oxide film. Since this capacitor has two or three trenches, an effective area sufficiently large for increasing a capacitance value of the capacitor can be obtained without increasing the plane area of the device. The conductive layer and the polysilicon are connected to aluminum interconnection layers through a silicide layer, so as to be connected to other integrated circuits.

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