Photoconductor Detector Modules IHDR

1. Photoconductor Detector Modules IHDR • ASTEQ-GmbH • GermanyPeter Dinges, Michael Harr, Heribert Krüger, Hilmar Richter, Bernd Zimmermann 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 Photoconductor Detector Modules

3. Leaf spring FO Pigtail FEE Harness <= Cavity => Cooling strap Completely Integrated High Stress Module Photoconductor Detector Modules

4. Integrated QM Modules with FEE 11 HS Modules and 12 LS Modules Photoconductor Detector Modules

5. RM Modules without FEE:13 HS Modules and 14 LS Modules 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. 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 Photoconductor Detector Modules

8. 25 Low Stress Modules 25 High Stress Modules 2.5 K 1.7 K 4 K 4 K 16 Detector Wires (Steel) 4 Long FEE + 2 Long Harness Posts (Kapton) 2 Short Harness Posts (Kapton) 11 µW 202 µW 134 µW 7 µW 162 µW 108 µW P = 375 µW P = 249 µW P = 624 µW 4 Thermal Budget Photoconductor Detector Modules

9. Slit Support Post Stability: Cryovibration Test Free bearing support post • 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. Photoconductor Detector Modules

10. 2 Ball segment Detector contact Ge:Ga crystal 1 Detector contact Insulator Gold wire 25 µm Detector Stack in the Cavity and Final Bias Design Detector Stack 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 Photoconductor Detector Modules

11. 30 mV Specification Cut-off Wavelength Specification high stress module: lCW > 200 µm @ 40 mV Specification low stress module: 125 < lCW <130 µm @ 100 mV Photoconductor Detector Modules

12. PA / QA Activities: Manufacturing Flow (PACS-NT-PL-003) Cleaning and incoming inspection of all mechanical module parts Preparation of FEE / harness support posts Incoming inspection of FEE / Harness / Pigtail Gluing of the pigtail and cooling strap to the harness substrate Implementation of connector saver and short circuit connector Detector stack assembly and RSR measurement. KIP: Check of detector stack KIP Cleaning of the module and check with UV light KIP Final check (with UV light) of the completed module before shipping Integration of FEE / harness substrate, completion of electricalwiring, fixing of FO 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 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 Photoconductor Detector Modules