Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Oxidation and Diffusion Resistance Structure for Capacitor Structure

IP.com Disclosure Number: IPCOM000103804D
Original Publication Date: 1993-Jan-01
Included in the Prior Art Database: 2005-Mar-18
Document File: 1 page(s) / 70K

Publishing Venue

IBM

Related People

Brady, MJ: AUTHOR [+5]

Abstract

Strontium Titanate or Barium Strontium Titanate material is proposed as a dielectric material to be used in high-density DRAM devices. The proposed thin film deposition process, such as sputtering or chemical vapor deposition, requires an oxygen atmosphere at a high temperature, in the range of 600oC or higher. Key to the fabrication of this structure is to prevent the interaction of the substrate (silicon or poly-silicon) during the formation of the high dielectric material, and prevent the interdiffusion of oxygen down into the silicon to avoid growing a lower value dielectric oxide. The barrier, in addition, must also be electrically conducting and inert. A new structure is disclosed to prevent silicon oxidation, oxygen diffusion as well as electromigration.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 57% of the total text.

Oxidation and Diffusion Resistance Structure for Capacitor Structure

      Strontium Titanate or Barium Strontium Titanate material is
proposed as a dielectric material to be used in high-density DRAM
devices.  The proposed thin film deposition process, such as
sputtering or chemical vapor deposition, requires an oxygen
atmosphere at a high temperature, in the range of 600oC or higher.
Key to the fabrication of this structure is to prevent the
interaction of the substrate (silicon or poly-silicon) during the
formation of the high dielectric material, and prevent the
interdiffusion of oxygen down into the silicon to avoid growing a
lower value dielectric oxide.  The barrier, in addition, must also be
electrically conducting and inert.  A new structure is disclosed to
prevent silicon oxidation, oxygen diffusion as well as
electromigration.

      The method disclosed utilizes a three-layer structure to allow
for the deposition of SrTiO3 or Bax Sr(1-x) TiO3 at a high
temperature.  The first layer in contact with Si or poly Si serves as
an adhesion layer.  The adhesion layer is a thin film of Cr, Ti, Ta,
or Co in the thickness range of 100 to 400 o . The second layer
serves as oxidation and diffusion barrier.  This layer consists of a
thin film alloy of a thickness ranging 1000 to 2000 o.  The thin film
alloy is made of a binary composition with a high oxidation resistant
matrix, such as Pt, Ir, Rh, and a minor alloying element (1-2 at.%),
such as B, Hf, or Ti. ...