1. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 1 IHDR ASTEQ-GmbH Germany Peter Dinges, Michael Harr, Heribert Krüger, Hilmar Richter, Bernd Zimmermann

2. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 2 Overview 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

3. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 3 Completely Integrated High Stress Module Leaf spring FO FEEHarness Pigtail Cooling strap

4. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 4 Integrated QM Modules with FEE 11 HS Modules and 12 LS Modules

5. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 5 RM Modules without FEE: 13 HS Modules and 14 LS Modules

6. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 6 Optical / 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.

7. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 7 Electrical 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

8. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 8 Thermal Budget 4 K P = 375 µW 4 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 Modules 2.5 K 1.7 K 4 K 16 Detector Wires (Steel) 4 Long FEE + 2 Long Harness Posts (Kapton) 2 Short Harness Posts (Kapton)

9. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 9 Support 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 LN 2 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

10. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 10 Detector 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

11. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 11 Specification Cut-off Wavelength Specification high stress module: CW > 200 µm @ 40 mV 30 mV Specification low stress module:  CW <130 µm @ 100 mV

12. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 12 PA / 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

13. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 13 Procurement 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

14. PACS IHDR 12/13 Nov 2003 Photoconductor Detector Modules 14 Summary 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