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 Data Analysis Sheet L.3

Data analysis sheet for in-plane linelength measurements with one end anchored

Top view of a cantilever test structure depicting the measurement to be made.

Figure L.3.1.  Top view of a cantilever 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 traces (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) = σxcal = µm
resolution of the interferometer in the x-direction = xres = µm
z
-calibration factor (for the given magnification) = calz =
alignment ensured ?   Yes      No
data leveled ?   Yes      No
                                      


INPUTS (uncalibrated values):
              x1max (i.e., x1upper) = µm
              x1min (i.e., x1lower) = µm        (x1min > x1max)
              x2min (i.e., x2upper) =
µm       (x2min > x1min)
              x2max (i.e., x2lower) =
µm       (x2max > x2min)
                                    

OUTPUTS (calibrated values):

            Lmin =  ( x2minx1min ) * calx µm
            Lmax = ( x2maxx1max ) * calx
µm
            L =  (Lmin + Lmax ) / 2 = µm
           
         uL = (Lmax Lmin ) / 6 = µm
                     uxcal = (σxcal / interx) * ( L / calx ) = µm
                     uxres
= xres * calx / 1.732 = µm
            uc = SQRT [ uL2 + uxcal2 + uxres2] = 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 σxcal should be between 0
µm and 4 µm.
    9.   The value for xres 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.   x1min should be greater than x1max.
  14.   x2min should be greater than x1min.
  15.   x2max should be greater than x2min.
  16.   The calibrated values for x1min and x1max are greater than 10
µm apart.
  17.   The calibrated values for x2min and x2max are greater than 10
µm apart.

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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