Data Analysis Sheet L.1

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Data analysis sheet for in-plane linelength measurements with two ends anchored

Top view of a fixed-fixed beam test structure depicting the measurement to be made.

Figure L.1.1. Top view of a fixed-fixed beam test structure depicting the measurement to be made.

To obtain the following measurements, consult ASTM standard test method E 2244 entitled
"Standard Test Method for In-Plane Length Measurements of Thin, Reflecting Films
Using an Optical Interferometer."

filename of 3-D data set (optional)   =
filename of 2-D data trace (optional) =
material = Poly1       Poly2      stacked Poly1 and Poly2
                 SiC-2      SiC-3
design length = µm
magnification = ×
orientation = 0 degree      90 degree
x-calibration factor (for the given magnification) = calx =
interferometer's maximum field of view (for the given magnification) = interx = µm
one sigma uncertainty in a ruler measurement (for the given mag) = σ_xcal = µm
resolution of the interferometer in the x-direction = x_res = µm
z-calibration factor (for the given magnification) = calz =
alignment ensured ?   Yes      No
data leveled ?   Yes      No

INPUTS (uncalibrated values):
              x1_max (i.e., x1_upper) = µm
              x1_min (i.e., x1_low_er) = µm      (x1_min > x1_max)
              x2_min (i.e., x2_low_er) = µm      (x2_min > x1_min)
              x2_max (i.e., x2_upp_er) = µm     (x2_max > x2_min)

OUTPUTS (calibrated values):
            L_min = ( x2_min – x1_min ) * calx = µm
            L_max = ( x2_max – x1_max ) * calx = µm
            L = (L_min + L_max ) / 2 = µm
                     u_L = ( L_max – L_min ) / 6 = µm
                     u_xcal = (σ_xcal / interx) * ( L / calx ) = µm
                     u_xres = x_res * calx / 1.732 = µm
            u_c = SQRT [ u_L² + u_xcal² + u_x_res²] = µm

Modify the input data, given the information supplied in any flagged statement below, if applicable, then recalculate:
    1.    Please fill out the entire form.
    2.    For the round robin test chip, the design length should be 25, 80, 200, 500, or 1000 mm.
    3. The measured value for L is more than 3u_c from the design length.
    4.    Is the magnification appropriate given the design length ?
    5.    Magnifications at or less than 2.5× shall not be used.
    6.    Is 0.95 < calx < 1.05 but not equal to "1" ? If not, recheck your x-calibration.
    7.    The value for interx should be between 0 µm and 1500 µm.
    8.    The value for σ_xcal should be between 0 µm and 4 µm.
    9.    The value for x_res should be between 0 µm and 1.57 µm.
10.    Is 0.95 < calz < 1.05 but not equal to "1" ? If not, recheck your z-calibration.
11.    Alignment has not been ensured.
12.    Data has not been leveled.
13.    x1_min should be greater than x1_max.
14. x2_min should be greater than x1_min.
15. x2_max should be greater than x2_min.
16. The calibrated values for x1_min and x1_max are greater than 10 µm apart.
17. The calibrated values for x2_min and x2_max are greater than 10 µm apart.

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NIST is an agency of the U.S. Commerce Department
The Semiconductor Electronics Division is within the Electronics and Electrical Engineering Laboratory.
The MNT Project (http://www.eeel.nist.gov/812/MNT/index.html) is within the Enabling Devices and ICs Group.

Date created: 12/4/2000
Last updated: 1/11/2008