Browse Prior Art Database

Ion Implantation for Preventing Ion Channeling

IP.com Disclosure Number: IPCOM000119936D
Original Publication Date: 1991-Mar-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 1 page(s) / 28K

Publishing Venue

IBM

Related People

Tobimatsu, K: AUTHOR

Abstract

This article describes a method for preventing ion channeling by implanting ions into silicon wafers from eight different directions.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Ion Implantation for Preventing Ion Channeling

      This article describes a method for preventing ion
channeling by implanting ions into silicon wafers from eight
different directions.

      In the manufacture of semiconductor devices, MOS FETs are
usually formed in (100) monocrystalline silicon wafers along (001)
and (010) directions.  When ions are implanted into the wafers along
a (001) or (010) direction at high incident angles, ion channeling
may be caused, resulting in variations in implantation depth.

      As shown in the figure, in this technique, ions are implanted
into the wafer from eight directions which make angles of (22.5 +
45n) degrees with a (001) or (010) direction, where n = 0 - 7.  One
eighth of a required total ion dose is implanted at each of the eight
angular positions.  By repeating the ion implantation eight times
while rotating the wafer 45 by 45 degrees, the total ion dose can be
achieved in the wafer with uniform implantation depth.