Data
analysis sheet for step height
measurements from one step
height test structure.
a)
b)
Figure SH.1.1.For a CMOS step height test
structure: a) a design rendition and
b) a cross-section.
To obtain the
following measurements, consult SEMI
standard test method MS2 entitled
"Test Method for Step Height
Measurements of Thin
Films."
date data
taken
(optional) =
/
/
Table 1 -
Preliminary
INPUTS
Data Set Prelims
Description
1
proc =
which process?
2
which =
which step height
measurement, test
structure, or quad?
3
orient =
orientation of the test
structure on the test
chip
4
×
magnification
5
align =
alignment ensured?
6
level =
data leveled?
7
µm
certified value of
physical step
height used for
calibration
8
µm
certified one sigma
uncertainty of the certified
physical step height
used for calibration
9
µm
maximum uncalibrated
range of the six
calibration measurements
taken before the data
session at the same
location on the physical step
height or after the
data session at the same
location on the physical step
height (whichever
is larger)
10
µm
the uncalibrated average
of the six calibration
measurements from which
zrepeat
was found
11
µm
uncalibrated drift in
the calibration data
(i.e., the uncalibrated
positive difference
between the average of
the six calibration
measurements taken
before the data session
at the same location on
the physical step height
and the average of the
six calibration
measurements taken
after the data session
at the same location on
the physical step height)
12
the
z-calibration
factor = the certified
value of the physical step height
divided by the
average of the twelve
calibration measurements
taken at the same
location on the physical
step height
13
%
if
applicable, over the
instrument's total scan
range, the maximum
percent deviation from linearity,
as quoted by the instrument
manufacturer (typically
less than 3%)
14
σ
µm
the uncalibrated surface roughness of
platNX measured as
the smallest of all the
values obtained for
σplatNXt.
(However, if the
surfaces of platNX, platNY,
and platNr all have
identical compositions,
then it is measured as
the smallest of all the
values obtained for
σplatNXt,
σplatNYt,
and
σplatNrDt
in which case
σroughNX=σroughNY.)
15
σ
µm
the uncalibrated surface roughness of
platNY measured as
the smallest of all the
values obtained for
σplatNYt.
(However, if the
surfaces of platNX, platNY,
and platNr all have
identical compositions,
then it is measured as
the smallest of all the
values obtained for
σplatNXt,
σplatNYt,
and
σplatNrDt
in which case
σroughNX=σroughNY.)
Nomenclature:
"N" refers to the
test structure number ("1,"
"2," "3,"
etc.),
"X" and "Y"
refer to the platform letter
("A," "B," "C,"
etc.),
"r" indicates a
reference platform,
"D" directionally
indicates which reference
platform, and
"t" indicates which
data trace ("a," "b,"
or "c").
Report the results as follows: Since it can be assumed that the
possible estimated values are either approximately uniformly
distributed or Gaussian with approximate standard deviation
uc, the step
height is believed to lie in the
interval stepNXY ±
uc with a level of
confidence of approximately 68 % assuming a Gaussian distribution.
Modify the input data,
given the information
supplied in any flagged
statement below, if
applicable, then
recalculate:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
σroughNX
and
σroughNY
should be greater than 0.0
µm and less than or
equal to the smallest
measured value for
σplatNXt
and
σplatNYt,
respectively.
13.
14.
15.
16.
σplatNXt
and
σplatNYt
should be between 0.00 µm
and 0.025 µm, inclusive.
