Ron Madaras, February 3, 2005

Summary of Survey Measurementsof 72 Modules

on 12 Production Pixel Sectors (9006-9017)

Ron Madaras, February 3, 2005

Modules-on-Sector Measurements

3 modules on front side.3 modules on back side.

3 mounting buttons glued inholes in carbon sector.

X=0,Y=0 is always left button,looking down on sector, foreach side.

Y

X

Front sector surface

Back sector surface

Button surface~700 microns

~4018 microns

(not to scale)

Ron Madaras, February 3, 2005

Modules-on-Sector Measurements

For each sector side we measure (using a SmartScope):1) X,Y of survey targets at the 4 corners of each module. Then calculate:

Delta X = Xmeaured - Xnominal, Delta Y = Ymeaured - Ynominal

2) 32 X,Y,Z points on the top of each module (16 along one long edge, 16along the other long edge). Fit the 32 points to a 3D module plane.Save: fit parameters, chi-square, residuals mean and residuals RMS.Calculate: Bow & Twist of module, & Height of module above sector plane.

3) 12 X,Y,Z points on the sector surface. Fit 12 points to a 3D sector plane.Save: fit parameters, chi-square, residuals mean and residuals RMS.(This is done 3 times for each side, each time a module is measured.)

4) 4 X,Y,Z points on the button surface, for each of 3 mounting buttons. Fit 12points to a 3D button plane.Save: fit parameters, chi-square, residuals mean and residuals RMS.(This is done 6 times per sector, each time a module is measured.)Compare sector plane and button plane.

Ron Madaras, February 3, 2005

Delta X, Delta Y of Module Survey Targets

Delta X and Delta Y of Survey Targets of Modules on Sectors(for 72 modules on 12 sectors, 9006-9017)

Mean: -2 micronsSigma: 4 microns

Mean: 0 micronsSigma: 3 microns

From fits:

Ron Madaras, February 3, 2005

Module Bow and Twist Measurements

Bow and Twist Measurements of Modules on Sectors(for 72 modules on 12 sectors, 9006-9017)

Average |Bow| = 8 microns RMS |Bow| = 6 microns

Average |Twist| = 0.8 mr RMS |Twist| = 0.7 mr

Ron Madaras, February 3, 2005

Module Height Above Sector Surface

For each of the 72 modules on the 12 sectors, calculate the height of the top of the module above the sector plane at the 32 measured points. Then:

a) Calculate the Tilt of each module with respect to the sector plane:Tilt = Module height at top of module - Module height at bottom

b) Calculate the Mean of the 32 heights and the RMS of the 32 heights for each Module. Compare Mean Height to Nominal Value (270 microns).

Average |Tilt| = 13 microns RMS |Tilt| = 11 microns

Average = 52 microns RMS = 10 microns

Average = 12 microns RMS = 4 microns

Ron Madaras, February 3, 2005

Comparison of Sector and Button Planes

At X=0,Y=0, calculate the Z difference between the sector and button planes:Zdiff = (Zsector-Zbutton) - Nominal Value

For the front sector plane: Zdiff = sector thickness + button thickness - 4018 (µm)For the back sector plane: Zdiff = -button thickness - (-700) (µm)

Average = 27 microns RMS = 8 microns

Average = -28 microns RMS = 7 microns

Results indicate actual button thickness is 28 microns greater than nominal.

Ron Madaras, February 3, 2005

Comparison of Sector and Button Planes

Non-parallelism of the sector and button planes:Non-parallelism = (Zsector-Zbutton)X,Y - (Zsector-Zbutton)0,0

Non-parallelism = 0 if the sector and button planes are parallel.

Measure non-parallelism for X=0,Y=-70 (along length of sector) X=70,Y=0 (along width of sector)

Since the buttons are distributed mainly in X, and not very much in Y, expectnon-parallelism along the length (Y) of the sector to be measured less preciselythan along the width (X) of the sector.

Non-parallelism is measured 3 times for the front sector plane and 3 times forthe back sector plane, once every time a module is measured. For a givennon-parallelism, sign conventions are such that if we measure it exactly:

For X=0,Y=-70: Av. front non-parallelism + Av. back non-parallelism = 0For X=70,Y=0: Av. front non-parallelism - Av. back non-parallelism = 0

A deviation from zero of these quantities indicates how well/poorly we measurethe non-parallelism. See plots of these 2 cases on the next page.

Ron Madaras, February 3, 2005

Comparison of Sector and Button Planes

Average = 41 microns RMS = 60 microns

Average = 4 microns RMS = 20 microns

As expected, the non-parallelism along the length (Y) of the sector ismeasured less precisely than along the width (X) of the sector.

Non-parallelism (NP) of the sector and button planes (continued)

Ron Madaras, February 3, 2005

Conclusions

Modules are glued to sectors with a position accuracy of 3.5 microns in X & Y!

For other measured quantities:

|Bow| 8 6 microns|Twist| 0.8 0.7 mr|Tilt| 13 11 micronsMean height above sector plane - Nominal 52 10 micronsRMS (Heights above sector plane) 12 4 micronsZdiff = (Zsector-Zbutton) - Nom

Front: 27 8 micronsBack: -28 7 microns

F + B Non-parallelism for X=0,Y=-70 41 60 micronsF + B Non-parallelism for X=70,Y=0 4 20 microns

Average RMS