Patent · US Expired

Sloped storage node for a 3-D dram cell structure

US5573979A · kind A · utility

43Cited by
4References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 13, 1995
Grant dateNov 12, 1996
Priority date
Expiry dateFeb 13, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/978
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Generally, the present invention utilizes dry plasma etching techniques such as Electron Cyclotron Resonance (ECR) to produce sloped sidewalls on a DRAM storage cell. The rounded corners of the lower electrode made by this technique allow the advanced dielectric material to be deposited without substantial cracking, and it also allows the capacitance to be closely predicted and controlled due to the uniformity in which the advanced dielectric layer can be fabricated. One embodiment of the present invention is method of making a microelectronic structure comprising a supporting layer (e.g. Si substrate 30) having a principal surface, a lower electrode overlying the principal surface of the supporting layer, and a high-dielectric-constant material layer (e.g. BST 44) overlying the top surface of the lower electrode. The lower electrode comprises a barrier layer (e.g. TiN 36), and an unreactive layer (e.g. Pt 42).

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