Ron Madaras, LBL, September 21, 2005 Page 1 of 11

Summary of Survey Measurementsof 252 Modules

on 42 Pixel Sectors (9006-9047)

Ronald J. MadarasLawrence Berkeley National Laboratory

September 21, 2005

Ron Madaras, LBL, September 21, 2005 Page 2 of 11

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, LBL, September 21, 2005 Page 3 of 11

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

• 32 X,Y,Z points on the top side of each module (16 along one long edge, 16 along the other long edge) in the vicinity of the first and last chip ID pads of each front-end chip.Calculate: Bow & Twist of module, & Height of module above sector plane.Fit 32 points to a 3D module plane; plot RMS of Z residuals from fit.

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 3 times for each side, each time a module is measured.)Compare sector plane and button plane.

Ron Madaras, LBL, September 21, 2005 Page 4 of 11

Delta X, Delta Y of Module Survey Targets

Delta X and Delta Y of Survey Targets of Modules on Sectors(for 252 modules on 42 sectors, 9006-9047)

Mean: -2.5 micronsSigma: 2.7 microns

Mean: -0.2 micronsSigma: 2.6 microns

From fits:

Ron Madaras, LBL, September 21, 2005 Page 5 of 11

Module Bow and Twist Measurements

Bow and Twist Measurements of Modules on Sectors(for 252 modules on 42 sectors, 9006-9047)

Average |Bow| = 7 microns RMS |Bow| = 6 microns

Average |Twist| = 0.7 mr RMS |Twist| = 0.6 mr

Average Bow = 3 microns RMS Bow = 9 microns

Average Twist = 0.0 mr RMS Twist = 0.9 mr

Bow Measurements(252 modules on 42 sectors)

0

10

20

30

40

50

60

70

-35 -25 -15 -5 5 15 25 35

Bow (microns)

Frequency

Twist Measurements(252 modules on 42 sectors)

0

10

20

30

40

50

60

70

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0

Twist (mr)

Frequency

Ron Madaras, LBL, September 21, 2005 Page 6 of 11

Module Plane Fits

Fit the 32 X,Y,Z points of a module surface to a 3D module plane. Plot here the RMS of the Z residuals from the fit, for each module:

Average = 8 microns RMS = 3 microns

RMS of Z Residuals of Plane Fits(252 modules on 42 sectors)

0

10

20

30

40

50

60

70

2 4 6 8 10 12 14 16 18

RMS (microns)

Frequency

It is seen that a 3D flat plane fit is good enough, as the RMS values of the Z residuals are small, and a circle fit or third order polynomial fit is not needed.

Ron Madaras, LBL, September 21, 2005 Page 7 of 11

Module Height Above Sector Surface

For each of the 252 modules on the 42 sectors, calculate the height of the top side 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 edge of module - Module height at bottom edge

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| = 14 microns RMS |Tilt| = 10 microns

Average = 53 microns RMS = 11 microns

Average = 11 microns RMS = 4 microns

Tilt Above Sector Plane(252 modules on 42 sectors)

0

10

20

30

40

50

60

70

-60 -40 -20 0 20 40 60

Tilt (microns)

Frequency

Mean Height Above Sector Plane - Nominal

(252 modules on 42 sectors)

0

10

20

30

40

50

60

70

25 35 45 55 65 75 85 95Mean - Nom (microns)

Frequency

RMS (Heights AboveSector Plane)

(252 modules on 42 sectors)

0

10

20

30

40

50

60

4 8 12 16 20 24 28RMS (microns)

Frequency

Ron Madaras, LBL, September 21, 2005 Page 8 of 11

Comparison of Sector and Button PlanesAt X=0,Y=0, calculate the Z difference between the sector and button planes:

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

Average = 23 microns RMS = 12 microns

Average = -9 microns RMS = 21 microns

Results indicate actual button thickness is ~16 microns greater than nominal.

(Zsector-Zbutton) - 4018for the Front Sector Plane126 modules on 42 sectors)

0

5

10

15

20

25

30

-15 0 15 30 45 60Zdiff

Frequency

(Zsector-Zbutton) - (-700)for the Back Sector Plane(126 modules on 42 sectors)

0

2

4

6

8

10

12

14

16

-40 -30 -20 -10 0 10 20 30 40Zdiff

Frequency

Ron Madaras, LBL, September 21, 2005 Page 9 of 11

Comparison of Sector and Button PlanesNon-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, expect non-parallelism along the length (Y) of the sector to be measured less precisely than along the width (X) of the sector.

Non-parallelism (NP) is measured 3 times for the front of the sector and 3 times for the back of the sector, once every time a module is measured. For a given non-parallelism of the sector and button planes, sign conventions are such that if we measure it exactly, the front and back non-parallelisms have opposite signs for X=0,Y=-70 and the same signs for X=70,Y=0. Thus:

For X=0,Y=-70: Average NP (of a sector) = (Front NP - Back NP)/2Front/Back NP “difference” = (Front NP + Back NP)/2 would be zero

For X=70,Y=0: Average NP (of a sector) = (Front NP + Back NP)/2Front/Back NP “difference” = (Front NP - Back NP)/2 would be zero

A deviation from zero of (Front NP +/- Back NP)/2 indicates how well or poorly we measure the non-parallelism.

Ron Madaras, LBL, September 21, 2005 Page 10 of 11

Comparison of Sector and Button Planes

Average = 12 microns, RMS = 26 microns

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

Average = -4 microns, RMS = 16 microns

Average = -1 microns, RMS = 8 microns

Average = 0 microns, RMS = 7 microns

42 Sectors 42 Sectors

42 Sectors 42 Sectors

Average NP for X=0,Y=-70

0

1

2

3

4

5

6

7

-45 -30 -15 0 15 30 45 60 75Average NP (microns)

Frequency

Average NP for X=70,Y=0

0

2

4

6

8

10

12

14

-45 -30 -15 0 15 30 45 60 75Average NP (microns)

Frequency

Front/Back NP diff for X=0,Y=-70

0

1

2

3

4

5

6

7

8

-45 -30 -15 0 15 30 45 60 75(Front NP + Back NP)/2 (microns)

Frequency

Front/Back NP diff for X=70,Y=0

0

2

4

6

8

10

12

14

16

-45 -30 -15 0 15 30 45 60 75(Front NP - Back NP)/2 (microns)

Frequency

Ron Madaras, LBL, September 21, 2005 Page 11 of 11

Conclusions for 252 Modules on 42 Sectors

Modules are glued to sectors with a position accuracy of 2.6 microns in X & Y!

For other measured quantities: Average RMS|Bow| 7 6 microns|Twist| 0.7 0.6 mrRMS Z residuals (plane fits) 8 3 microns|Tilt| 14 10 microns(Mean height above sector plane) - Nominal 53 11 micronsRMS (Heights above sector plane) 11 4 micronsZdiff = (Zsector-Zbutton) - Nom

Front: 23 12 micronsBack: -9 21 microns

Non-parallelism:X=0,Y=-70: Average 12 26 microns

(Front+Back)/2 -4 16 microns X=70,Y=0: Average -1 8 microns

(Front-Back)/2 0 7 microns