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 Data Analysis Sheet L.6

Data analysis sheet for in-plane deflection measurements from released part to fixed location

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

Figure L.6.1.  Top view of a portion of the pointer 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."


date data taken (optional) = / /

   
   
 
filename of 2-D data traces (optional) =
                                                              

Table 1 - Preliminary ESTIMATES

Description

1 material =       
      
 
      
 
   

material

2 displacement = µm

designed displacement

3 magnification = × magnification
4 orientation =        

   
orientation on the chip
5 calx = x-calibration factor (for the given magnification)
6 interx = µm interferometer's maximum field of view (for the given magnification)
7 σxcal = µm one sigma uncertainty in a ruler measurement (for the given magnification)
8 xres = µm resolution of the interferometer in the x-direction
9 calz = z-calibration factor (for the given magnification)
10 aligned?      alignment ensured ?
11 leveled?      data leveled ?


                                      

 

Table 2 - INPUTS (uncalibrated values)

Notes

12 x1max (i.e., x1lower) = µm  
13 x1min (i.e., x1upper) = µm (x1min > x1max)
14 x2min (i.e., x2lower) = µm        (x2min > x1min)
15 x2max (i.e., x2upper) = µm  (x2max > x2min)
       
16 sep = µm pixel-to-pixel spacing (for the given magnification)
17 which values?      Use 'lower' or 'upper' values for calculation ? 


                                            


OUTPUTS (calibrated values):

            D1-min =  ( x2minx1min ) * calx µm
            D1-max = ( x2maxx1max ) * calx µm

            D1 =  (D1-min + D1-max ) / 2 = µm
                    
uD = (D1-max D1-min ) / 6 = µm
                     uxcal = (σxcal / interx) * ( D1 / calx ) = µm
                     uxres
= xrescalx / 1.732 =
µm
            uc = SQRT [ uD2 + uxcal2 + uxres2] = µm

            D1low (using lower values) = ( x2lower x1lower ) * calx = µm
                     uD-low =
(2 * sep * calx) / 3 = µm
                     uxcal-low = (σxcal / interx) * ( D1low / calx= µm

            uclow = SQRT [ uD-low2 + uxcal-low2 + uxres2] = µm

            D1up (using upper values) = ( x2upper
x1upper ) * calx = µm
            
         uD-up = (2 * sep * calx) / 3 = µm
                     uxcal-up = (σxcal / interx) * ( D1up / calx= µm

            ucup = SQRT [ uD-up2 + uxcal-up2 + uxres2] = µm

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 deflection
is believed to lie in the interval D1 ± 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. Please fill out the entire form.
2. The designed displacement is typically 0.0 µm.
3. The measured value for D1 is 10 µm greater than the designed displacement.
4. Is the magnification appropriate given the value for D1 ?
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.
18. sep should be between 0 µm and 1.57 µm.

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Date created: 12/4/2000
Last updated: 6/2/2009