Quality Assurance of HPDs

Arjan .H.Heering Rochester, October 20’01

DC measurements-uniformity-bias behavior-HV and gain-leakage current of each pixel

AC measurements -Capacitance and depletion-AC and DC Crosstalk- signal to noise for single p.e.

HPD Quality Assurance

-DEP HV 1 hour under 15 kVleakage currentQuantum efficiency > 11%Pluse shapedark noise spectrum

-Minnesota

-DatabaseAll data from each tube will be accessible through the web

QA flow for each HPD in Minnesota

HV connector and 1Gohm resistor2 weeks of HV testing under 13 KVDEP

Alignment measurement

DC measurements in darkroom

AC measurement in 2 dedicated room

Alignment QA

Custom Alignment ring

FNAL Interface Cart and packaging

Alignment procedure

-We reference the HPD on the ceramic carrier

- All carriers are within 80 microns, square

-we have send go/no go Jigs to DEP (0.003 inch difference)

-we use 3 sizes (0.001 difference) of carriers

- the best fit will be used for alignment measurement

-x ,y , rot offset from normal is measured (+-10micron)

-each HPD get a compensated offset ring for:-size-x-offset-y-offset-rotation offset

-Alignment is measured again before shipment toFNAL

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X-offset in microns

before

after

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Y-offset in microns

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after

01234567

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Rotation-offset in mrad

before

after

HPD alignment before and after correction(8 tubes corrected)

2002 Test Beam HPDs

Minnesota will send the first production HPDs to FNAL

Delivery:

March 1 : 10 HPDs (HB)April 1: 10 HPDs (HE)May 1: 10 HPDs (HO?)

-Interface Carts Production start 1/1 2002We need the final routing forHE and HB( HO?)

- Cookies and alignment Support plates are already over budgetCan we use production ODUs for HE?