1. Report from CNM activities
Giulio Pellegrini
Centro Nacional de Microelectronica
Barcelona, Spain

2. Mask design spreading Diodes 2D 3x3 matrix Medipix2 Test structures
Atlas pixel
3d pads
strips
Test for SEM
Long strip
MOS
10x10 matrix
Pilatus

3. Layout 3 detectors have been bump bonded in VTT to a Medipix2 chip.
3 will be done soon

4. Fabricated detectors

5. Double sided 3D 250 μm p+ columns in 300 μm n-type substrate
First run is p-in-n:
250 μm p+ columns in 300 μm n-type substrate
Electrode fabrication:
ICP etching of the holes: Bosch process, ALCATEL 601-E
Holes partially filled with 3 µm LPCVD poly
Doping with P or B
Holes passivated with 2 µm TEOS SiO2
(all fabrication done in-house)
-Deep RIE-ICP.
Load-lock manual one 4” wafer
SF6 etching
C4F8 passivation
Cooled mechanical clamping :He-Ln2
Possibility of Cryogenic etching.
DRIE etch. Bosch process.
LPCVD poly depo
Doping with gas sources (P) or solid sources (B)
Passivation of the hole with oxide deposited with TEOS
Hole aspect ratio 25:1, diameter 10um
Note that the poly and TEOS layers reach the bottom of the hole and the B profile is smooth at the corners
3rd Workshop on Advanced Silicon Radiation Detectors
C. Fleta

6. Bump bonding at CNM
Small clean room class 100 at CNM dedicated to packaging: Flip chip, Wire bonding, CMP
Joint project with IFAE (High Energy Physics Institute)
Bump bonding machine Süss Microtech FC150
Installation finished last week
Bumping process ready: electrodeposited SnPb and SnAg
CMP G&P POLI-400L (Installation pending)

7. Holes etching

8. Poly filling
polysilicon

9. Doping of poly
Poly-n+
Si-n+

10. Poly etching

11. Second etching

12. Second poly filling

13. Final sample Si-n- Si-p+ Si-n+ SiO2 Poly-p+ Poly-n+ Al/Cu Passiv
Mask Levels
Back-window
N-DIFF
N-HOLES
P-HOLES
POLY
WINDOW
METAL
PASSIV
Bump bonding

14. 3D technology 10 m holes 55m pitch 90 minutes etching
300 m thick wafer
Aspect ratio 24:1

15. 3D technology
10um
45um

16. 3D technology
pixels
strips

17. Pixel configuration Polysilicon contact Opening in the passivation
P-type Hole
Metal

18. Medipix 2

19. Atlas pixels

20. Strips (DC coupled)
Pilatus
Test structures

21. Testing Irradiation with neutrons- please see Celeste´s talk
Charge collection- please see Celeste´s talk
Electrical characterization I-V and CV
Imaging- waiting for bump bonding

22. New Fabrication Run 8 wafers p-type 8 wafers n-type
In Fabrication, due for the end of June 2008

23. Thank you