Photoconductor Detector Modules 1

PACS IHDR 12/13 Nov 2003

Photoconductor Detector Modules

IHDR

• ASTEQ-GmbH • Germany

Peter Dinges, Michael Harr, Heribert Krüger, Hilmar Richter, Bernd Zimmermann

Photoconductor Detector Modules 2

PACS IHDR 12/13 Nov 2003Overview

• Completely Integrated Module• Integrated QM Modules with FEEs• RM Modules without FEEs

• Optical / Mechanical Module <=> Camera Housing Interface

• Module Design– Electrical Interface– Thermal Budget– Support Post Stability: Cryovibration Tests

• Detector Stack and Final Bias Design• Achieved Performance

– Cut-off Wavelengths• PA / QA Activities: Manufacturing Flow Plan

• Procurement of Parts for / Assembling of Flight Modules• Summary

Photoconductor Detector Modules 3

PACS IHDR 12/13 Nov 2003Completely Integrated High Stress Module

Leaf spring

<=

Cavity

=

>

FO

FEE Harness

Pigtail

Cooling strap

Photoconductor Detector Modules 4

PACS IHDR 12/13 Nov 2003Integrated QM Modules with FEE

11 HS Modules and 12 LS ModulesHS module QM 03 (LENS) has been cryovibrated

All modules did not have back-outs! QM 03 has seen 28x cool downs to 4 KQM HS with FEE

Module S/N FO QM FEE FEE "cycled" Pecularities Module repair 4 K Cool downs CryovibrytionFM 04 29 76 A02-038-15 n Scratches onto pixels 7, 8, 12, 14 PACS-NT-RR-026 4 nFM 11 56 104 A02-527-01 n Small longitudinal crack (?) over a

third of pixel 5 PACS-NT-RR-007 6 n

FM 14 79 82 A02-527-11 n Small scratches onto pixels 12, 14 n 4 nQM 04 36 84 A02-038-23 y - n 5 nQM 05 38 56 A02-038-28 y - n 11 nQM 07 42 90 A02-038-11 n - n 10 nQM 08 43 87 A02-038-25 n Scratch onto pixel 7,

scratches onto FEE substrate because of intensive R measurements

PACS-NT-RR-006 11 n

QM 09 44 88 A02-038-12 n Longitudinal crack over pixel 8 n 6 nQM 10 45 89 A02-038-13 n PACS-NT-GR-005 n 10

+ (25x to LN2)n

QM 11 33 93 A02-038-21 y Longitudinal crack over pixel 6 n 9 nQM 12 48 91 A02-038-10 n - n 6 n

QM LS with FEEFM 26 35 99 A02-038-16 n - PACS-NT-RR-010 6 nFM 27 58 92 A02-038-19 n - PACS-NT-RR-011 18 nFM 34 66 97 A02-038-22 n - PACS-NT-RR-001 12 nFM 39 71 105 A02-038-04 n - n 15 yFM 40 72 69 A02-038-05 n - n 11 yFM 41 73 100 A02-038-29 n - n 6 nFM 42 74 101 A02-038-30 n - PACS-NT-RR-012 11 nQM 20 28 98 A02-038-17 y - n 11 yQM 21 39 70 A02-038-20 y - n 12 nQM 22 40 71 A02-038-02 n - n 7 yQM 23 41 106 A02-038-03 n - n 7 yQM 24 46 72 A02-038-14 n - PACS-NT-RR-009 15

+ (25x LN2)n

Photoconductor Detector Modules 5

PACS IHDR 12/13 Nov 2003RM Modules without FEE: 13 HS Modules and 14 LS Modules

RM HSModule S/N FO Pecularities Module repair 4 K Cool downs Cryovibrytion

Dummy QM 19 20 86 Scratches onto pixels 8, 9 PACS-NT-RR-035 4 n

Dummy QM 01 10 63 Dummy without signal-bias wires PACS-NT-RR-034 10 nFM 01 49 108 Scratch onto pixel 2, residues onto pixels 3, 4, 14, glue dot

onto pixel 7; Resistor SHD # 1n 2

nFM 02 52 74 Scratches onto pixels 2, 7, 8, 16 n 4 nFM 03 30 57 Scratches onto pixels 1, 2, 11, 15 PACS-NT-RR-027 2 nFM 05 47 77 Scratches onto pixels 7; very small slit of detector contact

to the cavity wall of pixel 6PACS-NT-RR-028 2

nFM 06 53 52 Scratches onto pixels 11 PACS-NT-RR-029 2 nFM 07 50 78 - PACS-NT-RR-030 4 nFM 08 51 65 Scratch onto pixels 6, 7, 14, glue dot onto pixels 3, 9, 14 n 4 nFM 09 54 59 - PACS-NT-RR-031 4 nFM 10 55 60 - PACS-NT-RR-032 2 nFM 13 58 61 Scratch onto pixels 1, 9 ,11 PACS-NT-RR-033 2 nFM 15 80 62 Scratch onto pixels 2, 7 2 nFM 16 86 102 Scratch onto pixels 2, 16 2 nRM LSFM 28 60 53 Small longitudinal crack (?) onto pixel 7,

scratches onto pixels 8, 14, 15PACS-NT-RR-013 18 n

FM 29 61 96 Small longitudinal crack (?) onto pixels 9, 15, scratches onto pixels 3, 6, 14, 15

PACS-NT-RR-014 12 n

FM 30 62 103 Scratch onto pixels 2, 6 PACS-NT-RR-015 8 nFM 31 63 66 Scratch onto pixels 9, 10 PACS-NT-RR-016 2 nFM 32 64 67 Scratch onto pixels 3 PACS-NT-RR-017 2 nFM 33 65 68 - PACS-NT-RR-018 12 nFM 35 67 58 Resistor SHD # 2 PACS-NT-RR-019 4 nFM 36 68 55 - PACS-NT-RR-020 2 nFM 37 69 80 Scratch onto pixels 5 PACS-NT-RR-021 2 nFM 38 70 81 Scratch onto pixels 7, 10 PACS-NT-RR-022 4 nFM 43 75 54 Scratch onto pixel 2, glue dot onto pixel 1 PACS-NT-RR-025 4 n

FM 44 76 107 Scratch onto pixel 11 PACS-NT-RR-024 2 nFM 45 77 64 - PACS-NT-RR-023 4 n

Photoconductor Detector Modules 6

PACS IHDR 12/13 Nov 2003Optical / Mechanical Module <==> Camera Interface

Radial arrangement of 25 high stress modules in groups of 5 modules. The centre of the radial arrangement is 240 mm in front of the fore optics in the plane of the pupil.

Photoconductor Detector Modules 7

PACS IHDR 12/13 Nov 2003Electrical Interface

Interface design• The nano connector of the pigtail harness is glued to the harness substrate• Thermal loads from the CRE flow via the Au wires between FEE and harness through the cooling strap

to the 4 K level• To minimalise thermal load to the module:

– Kapton supports for FEE and harness substrate – All wires from the module to electrical interface parts are stainless steel;

• Problem under investigation: Ca. 5% of measured pixels “strange”! Contact resistance (?) between stainless steel wire and H20E

Photoconductor Detector Modules 8

PACS IHDR 12/13 Nov 2003Thermal Budget

4 K

P = 375 µW

P = 624 µW

11 µW 202 µW 162 µW 7 µW 134 µW 108 µW

P = 249 µW

25 High Stress Modules 25 Low Stress Modules2.5 K1.7 K

4 K

16 Detector Wires (Steel)

4 Long FEE + 2 Long Harness Posts (Kapton)

2 Short Harness Posts (Kapton)

Photoconductor Detector Modules 9

PACS IHDR 12/13 Nov 2003Support Post Stability: Cryovibration Test

• 200 um Slit between kapton tube and support part (no gluing) at the free bearing support posts:

- Compensation of thermal expansion coefficient for different materials (module, FEE/harness substrate, kapton tube, etc.) during cool-down.

- After cool-down: slit = 0 - 50 um.

• Static tests at LN2 temperatures: Design withstands forces corresponding up to accelerations of 110 g.

• Above support post design passed cryo cycling and vibration tests with qualification load levels.

Free bearing support post

Slit

Photoconductor Detector Modules 10

PACS IHDR 12/13 Nov 2003Detector Stack in the Cavity and Final Bias Design

Ball segment

Detector contact

Ge:Ga crystal

Detector contact

Gold wire 25 µm

Insulator

Final design• Bias concept has been changed to avoid detector short

circuiting– Contact diameter decreased at the ball segment

side to prevent grounding of the signal line (2) – Contact diameter increased at the ground side

(this contact is grounded directly to the module (1)

Slits reduced from 30 - 70 µm to 10 - 40 µm and therefore less cross talk

1

2

Detector Stack

Photoconductor Detector Modules 11

PACS IHDR 12/13 Nov 2003Specification Cut-off Wavelength

Specification high stress module: CW > 200 µm @ 40

mV

30 mV

12 14 16 18 20 22 24

125

130

135 Min Max

CW

(µm

)QM # - LS

Specification low stress module: CW <130 µm

@ 100 mV

Photoconductor Detector Modules 12

PACS IHDR 12/13 Nov 2003PA / QA Activities: Manufacturing Flow (PACS-NT-PL-003)

KIP

Final check (with UV light) of the completed

module before shipping

Detector stack assembly and

RSR measurement.

KIP: Check of detector stack

KIP

Cleaning of the module and check

with UV light

Preparation of FEE / harness support posts

Gluing of the pigtail and cooling strap to the harness substrate

Implementation of connector saver and short circuit connector

Integration of FEE / harness substrate,

completion of electricalwiring,

fixing of FO

Incoming inspection of

FEE / Harness / Pigtail

Cleaning and incoming inspection of all

mechanical module parts

Photoconductor Detector Modules 13

PACS IHDR 12/13 Nov 2003Procurement of Parts for / Assembling of Flight Modules

• Status of parts procurement for Flight Modules

- Procurement of small parts nearly finished

- Delivery of FM FEEs starts end of November 2003

- Delivery of the pigtail from Cannon beginning of December 2003

- Procurement of FOs scheduled for December 2003 problem: Au coating not yet acceptable, solution mid November

- Procurement of module bodies initiated (delay about 2 month)

• Stack assembly of Flight Modules could starts around mid November if the pixel selection rule is confirmed by MPE

• First sixpack not before end of January 2004

• Funding of Flight modules assured only until the end of 2. sixpack (end of February 2004)

Time critical: Procurement / Assembly of

Modules

Photoconductor Detector Modules 14

PACS IHDR 12/13 Nov 2003Summary

• Interfaces to MPE housing, KT board and IMEC FEE and harness substrate defined

• Module design finished (specifications fulfilled) but: Pending problem of Contact resistance (?) between stainless steel wire and H20E glue

• Manufacturing of Flight Modules Initiated but: Pixel selection rule to be confirmed