Patent · US Expired

Method for fabricating a stack capacitor

US6004859A · kind A · utility

11Cited by
5References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 16, 1999
Grant dateDec 21, 1999
Priority date
Expiry dateFeb 16, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/964

Abstract

A method for fabricating a stack capacitor with a hemi-spherical grain (HSG) structure is provided. A dielectric layer with a cave is first formed on a substrate. A conformal multi-layer amorphous silicon layer with low dopant concentration is formed over the substrate to cover the cave surface. An amorphous silicon layer with a sufficiently high dopant concentration is formed on the multi-layer amorphous silicon layer to fill the cave. After a planarization process, a remaining portion of the multi-layer amorphous silicon layer and the amorphous silicon layer form a storage node to fill the cave. The dielectric layer is removed to expose the storage node. A HSG is formed on the exposed surface of the storage node. An annealing process is performed to obtain a uniform dopant concentration. A dielectric thin film is formed over the storage node and the HSG layer. An upper electrode is formed to accomplish the stack capacitor.

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