Browse Prior Art Database

Insulating Layer Modification for Directed Flux Cathode

IP.com Disclosure Number: IPCOM000121141D
Original Publication Date: 1991-Jul-01
Included in the Prior Art Database: 2005-Apr-03
Document File: 2 page(s) / 72K

Publishing Venue

IBM

Related People

Cuomo, JJ: AUTHOR [+3]

Abstract

A modification of a sputter target (cathode) surface has recently been developed. It utilizes the microstructure of a cathode surface to modify the emission distribution of atoms sputtered from the cathode or target surface. The surface is machined or formed such that there are a large number of narrow, deep openings. If the narrowest opening was less that two times the width of the plasma dark space, ions from a plasma enter the holes at perpendicular incidence and sputter the bottom surface. The emitted atoms are then collimated by the walls of the hole, and only atoms emitted approximately perpendicular to the original surface are emitted. The shape of the hole is not important and cross sections of circular, square, and rectangular holes, as well as hexagonal holes, were disclosed.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 67% of the total text.

Insulating Layer Modification for Directed Flux Cathode

      A modification of a sputter target (cathode) surface has
recently been developed.  It utilizes the microstructure of a cathode
surface to modify the emission distribution of atoms sputtered from
the cathode or target surface.  The surface is machined or formed
such that there are a large number of narrow, deep openings.  If the
narrowest opening was less that two times the width of the plasma
dark space, ions from a plasma enter the holes at perpendicular
incidence and sputter the bottom surface.  The emitted atoms are then
collimated by the walls of the hole, and only atoms emitted
approximately perpendicular to the original surface are emitted.  The
shape of the hole is not important and cross sections of circular,
square, and rectangular holes, as well as hexagonal holes, were
disclosed.

      The upper areas between the holes, which constituted the
original planar surface of the cathode, also contribute to the flux
of sputtered atoms emitted from the cathode or target.  Atoms emitted
from these upper, flat areas are not collimated and are emitted in a
broader, non-perpendicular distribution.

      The improvement to the above cathode structure described here
reduces this effect substantially.  By covering the top surfaces of
these self-collimated targets or cathodes with an insulator,
sputtering is largely suppressed at these surfaces.  Normally,
covering the cathode surface with an insu...