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 Data Analysis Sheet RS.1

Data analysis sheet for residual strain measurements

Top view of fixed-fixed beam used to measure residual strain.

Figure RS.1.1.  Top view of fixed-fixed beam used to measure residual strain.

To obtain the following measurements, consult ASTM standard test method E 2245 entitled
"Standard Test Method for Residual Strain 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   
(therefore, t =  µm )
design length = µm
which fixed-fixed beam on the round robin test chip ?  First    Second     Third   
magnification = ×
orientation =  0 degree      90 degree
x
-calibration factor (for the given magnification) = calx =
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 =
certified value of step height standard = cert = µm
standard deviation of step height measurements (on double-sided step height standard) = σzcal = µm
resolution of the interferometer in the z-direction = zres = µm
peak-to-valley roughness of a flat and leveled surface of the sample material calculated to be the average of three or more measurements, each measurement of which is taken from a different 2-D data trace = Rtave = µm
alignment ensured ?   Yes      No
data leveled ?   Yes      No
Is this fixed-fixed beam exhibiting stiction ?   Yes      No
           
If it is exhibiting stiction, do not fill out the remainder of this form.
     
                                     

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

INPUTS (uncalibrated values from Trace "b"):
              x1F = µm    z1F = µm   (x1ave < x1F * calx)
              x2F = µm    z2F = µm   (inflection point)
                                                                                           ( x1F < x2F < x3F )
              x3F = µm    z3F = µm   (most deflected point)
                                                                                          ( x1S = x3F ; z
1S = z3F )
              x2S = µm    z2S = µm   (inflection point)
              x3S = µm    z3S = µm   ( x3S * calx < x2ave )
                                                                                          ( x1S < x2S < x3S )

INPUTS (uncalibrated values from Trace "c"): 
              x1F = µm    z1F = µm   (x1ave < x1F * calx)
              x2F = µm    z2F = µm   (inflection point)
                                                                                           ( x1F < x2F < x3F )
              x3F = µm    z3F = µm   (most deflected point)
                                                                                           
( x1S = x3F ; z1S = z3F )
              x2S = µm    z2S = µm   (inflection point)
              x3S = µm    z3S = µm   ( x3S 
* calx < x2ave )
                                                                                           ( x1S < x2S < x3S )

INPUTS (uncalibrated values from Trace "d"): 
              x1F = µm    z1F = µm   (x1ave < x1F * calx)
              x2F = µm    z2F = µm   (inflection point)
                                                                                          ( x1F < x2F < x3F )
              x3F = µm    z3F = µm   (most deflected point)
                                                                                        
   ( x1S = x3F ; z1S = z3F )
              x2S = µm    z2S = µm   (inflection point)
              x3S = µm    z3S = µm   ( x3S  * calx < x2ave )
                                                                                           ( x1S < x2S < x3S )


                                      

OUTPUTS (calibrated values):

   
        x1ave µm            x2ave µm
             L      µm
 
                        Lmax = ( x2max x1max ) * calx
                         L
min = ( x2min
x1min ) * calx
                         uLL  =  ( Lmax Lmin ) / 6 =  µm
                         uLxcal  = ( σxcal / interx ) * ( L / calx ) = µm

                         uLxres  
= xres* calx / 1.732 =  µm

             u
cL   =
 SQRT[uLL2 + uLxcal2 + uLxres2 µm
             s                          from Trace "c"
                         s = 1       (for downward bending fixed-fixed beams)
                         s =
−1     (for upward bending fixed-fixed beams)

                             AF    µm      from Trace "b"
                           w1F       
        from Trace "b"
                             AS   µm      from Trace "b"
                           w3S   =              from Trace "b"

             xeF    µm            from Trace "b"
             xeS    µm   
         from Trace "b"
           
εr0    × 10-6       from Trace "b"
            εr     =    × 10
-6       from Trace "b"

                             AF    µm      from Trace "c"
                           w1F               from Trace "c"
                             AS   µm      from Trace "c"
                           w3S   =              from Trace "c"

             xeF    µm             from Trace "c"
             xeS    µm             from Trace "c"
            
εr0    × 10-6        from Trace "c"
             εr    =    × 10-6        from Trace "c"
                         usamp    =    × 10-6      from Trace "c"
                         uW    
=    × 10-6          from two or three traces
                         uxcal    =    × 10-6        from Trace "c"
                         uL    =    × 10-6           from Trace "c"
                         uzcal    =    × 10-6        from Trace "c"
                         uzres    
=    × 10-6        from Trace "c"
                         uxres    
=    × 10-6        from Trace "c"
                         uxresL    
=    × 10-6        from Trace "c"

             uc    
= SQRT[u
samp2 + uW2 + uxcal2 + uL2 + uzcal2 + uzres2 + uxres2 + uxresL2]
             uc    =    × 10-6        from two or three traces

                             AF    µm      from Trace "d"
                           w1F       
        from Trace "d"
                             AS   µm      from Trace "d"
                           w3S   =              from Trace "d"

             xeF    µm             from Trace "d"
             xeS    µm             from Trace "d"
            εr0    × 10
-6        from Trace "d"
            εr     =    × 10
-6        from Trace "d"


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 thickness value is different than what the fabricator specified.
    3.   For the round robin test chip, the design length should be 400, 450, 500, 550, 600, 650, 700, 750, or 800 mm. 

    4.   The measured value for L is more than 3ucL from the design length.
    5.   Is the magnification appropriate given the design length ?
    6.   Magnifications at or less than 2.5× shall not be used.
    7.   Is 0.95 < calx < 1.05 but not equal to "1"?  If not, recheck your x-calibration.
    8.   The value fo
r interx should be between 0 µm and 1500 µm.
    9.   The value fo
r σxcal should be between 0 µm and 4 µm.
  10.   The value fo
r xres should be between 0 µm and 1.57 µm.
  11.   Is 0.95 < calz < 1.05 but not equal to "1" ?  If not, recheck your z-calibration.
  12.   The value fo
r σzcal should be between 0 µm and 0.050 µm.
  13.   The value for cert should be greater than 0 µm and less than 25 µm.
  14.   The value for zres should be greater than 0 µm and less than or equal to 0.005 µm.
  15.   The value fo
r Rtave should be between 0 µm and 0.100 µm.
  16.   Alignment has not been ensured.
  17.   Data has not been leveled.

  18.   x1min should be greater than x1max.
  19.  x2min should be greater than x1min.
  20.   x2max should be greater than x2min.
  21.   The calibrated values for x1min and x1max are greater than 10 µm apart.
  22.   The calibrated values for x2min and x2max are greater than 10 µm apart.
  23.   In Traces "b," "c," and "d," the value for s is not the same.
  24.   x1ave should be < (x1F * calx) in all traces.
  25.   (x3S * calx) should be < x2ave in all traces.
  26.   In all traces, make sure ( x1F < x2F < x3F ).
  27.   In all traces, make sure ( x1S < x2S < x3S ).
  28.   For Trace "b," | [(x2F*calx) − xeF ] | = µm.  This should be < 5 µm.
                     If it is not, choose (x
2F, z2F) such that (x2F * calx) is closer to xeF = µm.
  29.   For Trace "b," | [(x2S*calx) −
xeS ] | =  µm.  This should be < 5 µm.
                     If it is not, choose (x
2S, z2S) such that (x2S * calx) is closer to xeS = µm.
  30.   For Trace "c," | [(x2F*calx) − xeF ] | = µm.  This should be < 5 µm.
                     If it is not, choose (x
2F, z2F) such that (x2F * calx) is closer to xeF = µm.
  31.   For Trace "c," | [(x2S*calx) −
xeS ] | =  µm.  This should be < 5 µm.
                     If it is not, choose (x
2S, z2S) such that (x2S * calx) is closer to xeS = µm.
  32.   For Trace "d," | [(x2F*calx) − xeF ] | =  µm.  This should be < 5 µm.
                     If it is not, choose (x
2F, z2F) such that (x2F * calx) is closer to xeF = µm.
  33.   For Trace "d," | [(x2S*calx) − xeS ] | =  µm.  This should be < 5 µm.
                     If it is not, choose (x
2S, z2S) such that (x2S * calx) is closer to xeS = µm.

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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