1. Ceramic Focal Plane Components For SNAP B. C
Ceramic Focal Plane Components For SNAP B. C. Bigelow, UM Physics 4/13/05

2. Ceramic Detector Packages
AlN detector package material already demonstrated
Ground and space heritage well established
Cryo epoxies known, package assembly procedures established
See Oluseyi, Bercovitz, et. al. (LBNL)
Package assembly to set height, flatness to ~ +/- 5 microns
See Miyazaki, et al, PASJ
AlN CTE close match to Si, SiC, Invar
Natural match to Si CCD sensor material
Near-match to HgCdTe Si MUX material
Can be machined, polished, epoxy-inserted, etc.
AlN -> near match for SiC
SiC package material base-lined for GAIA mission
More later!
04/13/05
Bruce C. Bigelow -- UM Physics

3. CTE for Focal Plane Materials
CTE plot courtesy of Pat Jelinsky:
04/13/05
Bruce C. Bigelow -- UM Physics

4. Bruce C. Bigelow -- UM Physics
Subaru Suprime Camera
On Subaru 8.2m telescope, Mauna Kea, Hi
See Miyazaki, et al
5 x 2 mosaic of LL-MIT 2K x 4k CCDs - 83 Megapixels
AlN CCD packages
AlN cold-plate
Assembled mosaic is flat to approx. +/- 5 microns
Threaded studs epoxied into AlN packages
Flat interface between packages and cold-plate
04/13/05
Bruce C. Bigelow -- UM Physics

5. Bruce C. Bigelow -- UM Physics
Subaru Suprime Camera
Miyazaki, et al
04/13/05
Bruce C. Bigelow -- UM Physics

6. Bruce C. Bigelow -- UM Physics
Subaru Suprime Camera
AlN cold-plate
120mm x 150mm mosaic
04/13/05
Bruce C. Bigelow -- UM Physics

7. Bruce C. Bigelow -- UM Physics
Subaru Suprime Camera
AlN package and “buffer block”
Stud is epoxied into AlN buffer block
04/13/05
Bruce C. Bigelow -- UM Physics

8. Bruce C. Bigelow -- UM Physics
Subaru Suprime Camera
AlN buffer block and spacer shims in assembly jig
04/13/05
Bruce C. Bigelow -- UM Physics

9. Bruce C. Bigelow -- UM Physics
Subaru Suprime Camera
AlN CCD package epoxied to buffer block
04/13/05
Bruce C. Bigelow -- UM Physics

10. GAIA mission SiC focal plane
Boostec SiC material:
Sintered fabrication process
Less than 3% porosity
Pure, alpha phase SiC, no free silicon
Boostek SiC Moly
Density: kg/m^3 10,200 kg/m^3
Young’s modulus: GPa 330 GPa
Flexural strength: 450 Mpa 415 Mpa
CTE (room temp): 4.0 PPM/C PPM/C
Thermal conductivity: 180 W/m·k 138 W/m·k
04/13/05
Bruce C. Bigelow -- UM Physics

11. GAIA mission SiC cold-plate
Boostec/Astrium GAIA focal plane demonstrator model:
Sintered SiC, 770mm by 580mm by 36mm, 8kg.
04/13/05
Bruce C. Bigelow -- UM Physics

12. GAIA mission SiC cold-plate
GAIA cold-plate - detector mounting detail.
Note finished bores on mounting holes
04/13/05
Bruce C. Bigelow -- UM Physics

13. Ceramic CCD Packages for SNAP
CCD package features:
All dimensions and mounting features per ICD AC14A (HDH)
Hypertonics KA series connectors per ICD
All vented hardware – but not always shown!
AlN PCB interfaces between detectors and connectors
Integral filter/aperture assemblies
AlN or SiC package and mount material (interchangeable)
04/13/05
Bruce C. Bigelow -- UM Physics

14. Bruce C. Bigelow -- UM Physics
Ceramic CCD package
Invar inserts with internal threads for M3 mounting screws
04/13/05
Bruce C. Bigelow -- UM Physics

15. Bruce C. Bigelow -- UM Physics
Ceramic CCD package
Round insert, diamond insert, undersized insert provide kinematic constraint of in-plane DOF – X, Y, and rot Z.
Ground pads define tip, tilt, and piston of package
04/13/05
Bruce C. Bigelow -- UM Physics

16. Bruce C. Bigelow -- UM Physics
Ceramic CCD assembly
AlN or SiC mount
AlN or SiC CCD package
epoxy
Ribbon cable
Invar insert, epoxied in
PCB
Invar insert, epoxied in
Hypertronics KA series, 72 pins
04/13/05
Bruce C. Bigelow -- UM Physics

17. Bruce C. Bigelow -- UM Physics
Ceramic CCD package
CTE-matching filter frame, with filter and aperture mask
04/13/05
Bruce C. Bigelow -- UM Physics

18. Bruce C. Bigelow -- UM Physics
Ceramic MCT Packages
MCT package features:
All dimensions and mounting features per ICD AC14A (HDH)
Hypertonics KA series connectors per ICD
All vented hardware – but not always shown!
AlN PCB interfaces between detectors and connectors
Integral filter/aperture assemblies
AlN or SiC package and mount material (interchangeable)
04/13/05
Bruce C. Bigelow -- UM Physics

19. Bruce C. Bigelow -- UM Physics
Ceramic MCT package
Near-copy of CCD PCB, but wraps around for wire-bonding to sensor MUX on top surface
AlN/SiC PCB isolates detector package from connector thermal stresses
04/13/05
Bruce C. Bigelow -- UM Physics

20. Bruce C. Bigelow -- UM Physics
Ceramic MCT package
04/13/05
Bruce C. Bigelow -- UM Physics

21. Bruce C. Bigelow -- UM Physics
Ceramic MCT package
Filter frame clearance for wire-bonds
04/13/05
Bruce C. Bigelow -- UM Physics

22. Bruce C. Bigelow -- UM Physics
Ceramic MCT package
04/13/05
Bruce C. Bigelow -- UM Physics

23. Bruce C. Bigelow -- UM Physics
SNAP ¼ CCD+MCT mosaic
CCD MCT
04/13/05
Bruce C. Bigelow -- UM Physics

24. Bruce C. Bigelow -- UM Physics
SNAP ¼ CCD+MCT mosaic
Section showing mounting interface details
04/13/05
Bruce C. Bigelow -- UM Physics

25. Bruce C. Bigelow -- UM Physics
SNAP ¼ CCD+MCT mosaic
Section showing mounting interface details
04/13/05
Bruce C. Bigelow -- UM Physics

26. Bruce C. Bigelow -- UM Physics
SNAP ¼ CCD+MCT mosaic
Back side of FP mosaic showing mounting screws and access to connector
04/13/05
Bruce C. Bigelow -- UM Physics