Browse Prior Art Database

Haze Mode for Measuring Size and Density of Silicon Nucleation Sites on Oxide

IP.com Disclosure Number: IPCOM000107576D
Original Publication Date: 1992-Mar-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 1 page(s) / 46K

Publishing Venue

IBM

Related People

Kuge, HH: AUTHOR

Abstract

Disclosed is a method which is suitable for quantitatively determining the nucleation of silicon on oxide and the dependency of silicon nucleation by measuring the amount of light reflected from the wafer surface.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 71% of the total text.

Haze Mode for Measuring Size and Density of Silicon Nucleation Sites on Oxide

       Disclosed is a method which is suitable for
quantitatively determining the nucleation of silicon on oxide and the
dependency of silicon nucleation by measuring the amount of light
reflected from the wafer surface.

      One of the major types of electrical shorts in 4 Mbit chips are
electrical connections over an electrically isolating spacer of CVD
(chemical vapor deposition) oxide (TEOS (tetra ethyl ortho silicate)
oxide).  Such OSSs (over the spacer shorts) are supposed to be caused
by silicon being deposited on the TEOS spacer during a selective
epitaxial process.

      Nucleation of oxides during epitaxial Si deposition starts with
the growth of small grains, the size and density (grains/cm2) of
which depend on the deposition conditions.

      Measurements are carried out with a tool which is normally used
to measure particles.  This tool determines the amount of incident
laser light reflected from a wafer surface.  For particle
measurements, the tool locates the centers of stray light.

      The disadvantage of this method is that the small size (about
0.1 mm) of the silicon grains grown during a typical production
process is below the detection limit of the tool used in the
particle-counting mode.  In the haze mode, any diffuse reflected
stray light is measured in parts of the incoming light, so that the
haze is a measure of the size and especially the de...