1. — Test board for CBM01B2 baby detectors — Anton Lymanets & Johann Heuser CBM collaboration meeting GSI, 27 February 2008 Microstrip detector testing at GSI

2. Detector CBM01B2 256  256 orthogonal strips; 50.7 µm pitch; AC readout; 285 µm thick Dimensions: 1.56  1.56 cm 2

3. test global detector characteristics e.g. IV, CV access both detector sides contact a few strips for detailed measurements, including n-XYTER readout do all this as quickly and as simple as possible Let’s make a test board

4. Read-out CBM01B2 sensor (“small baby”, 50.7 μm pitch) Read-out 32 strips in the middle of sensor on both sides Ultrasonic wedge bonding PCB → sensor Ordinary line density Two test zones 1 cm 2 each for adjustment of bonding head Standard ERNI 114805 connector to n-XYTER kit Test board PCB: Standard manufacturing limits in particular the pitch size of the bonding pads: 200 µm line pitch Wire bonding: Max. recommended bond wire length @ 50 µm pitch: ~ 2.5 mm Fan-out bond pattern required. Max. opening angle: ~ 40 deg Advice from: H. Deppe (bonding, PCB) R. Lalik (connection to n-XYTER board)

5. PCB top side PCB bottom side 100 mm 70 mm 100 mm pad 10 x 10 mm 2 copper with chemical gold opening for detector legs bias pads SMD 1 M , 4 x total

6. 15.6 mm "balcony" 15.6 mm 15.0 mm 1.6 mm 15.6 mm PCB bond wire "balcony" PCB glue 0.3 mm detector 0.6 mm 1.0 mm Opening in PCB for detector mounting Top view Side view

7. 4 bias pads Connector: ERNI model 114805 Dual row, male, type B Pins: 68 (unused pins marked red) Height: 8.2 mm Size: ~(6.3×46.3) mm 2 Pin pitch: 1.27 mm (both x and y) Four 1MΩ resistors http://www.erni.com/smc.htd?gID=4654590

8. PCB to Si sensor bonding Pads layout at PCB: Line width: 100 μm 2 (no pads) Pitch: 200 μm PCB CBM01B2 Max angle: 51° Max bond length: 3.3 mm

9. Mechanical mounting of the detector "balcony" ~ 1.6 mm ~ 1.5 cm ~ 300 µm "balcony" PCB glue bond wire

10. PCB Layout Layout made by P. Skott

12. Metal support structure to support PCB and sensor during bonding 100 12 50 120

13. Conclusions & work plan Design finished, Layout finished Production @ ILFA, Hannover: ongoing (incl. gold plating, machining of hole) Weeks 8, 9, 10 2008 Al bonding fixture: to be manufactured Setup of testing station in C27 (Power supply, etc.)