Patent · US Expired

Method of fabricating a capacitor structure for a dynamic random access memory

US5913129A · kind A · utility

17Cited by
4References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 12, 1998
Grant dateJun 15, 1999
Priority date
Expiry dateJan 12, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D1/716

Abstract

A method of fabricating a capacitor structure for a dynamic random access memory. This method comprises the following steps: a transistor is provided on a semiconductor substrate, and spacers are formed over the sidewalls of a gate electrode of the transistor. A first oxide layer is formed over the transistor. A bit line is deposited to contact with the source region of the transistor. Thereafter, a second oxide layer is formed over the bit line. A contact opening is formed exposing the drain region. Then the hemispherical grained silicon layer is formed into the contact opening. A polysilicon layer is formed over the hemispherical grained silicon layer. Therefore both the hemispherical grained silicon layer and the third polysilicon layer have rough surfaces. Subsequent conventional processes for the complete formation of capacitor structure are performed. It is therefore the capacitor maintains a required capacitance while reducing the horizontal dimensions of the storage capacitor.

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