Design and development of thin double side silicon

microstrip sensors for CBM experiment

Mikhail MerkinSkobeltsyn Institute of Nuclear Physics

Moscow State University

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

Sensor Geometry

– According simulation optimal sensors size for central part, because very hard radiation environment and high multiplicity - 40 • 60 mm2

– Strip pitch for both sides - 58 μm– Stereoangle - ±7.5о

– Number of strips on both sides - 1024 – Number of readout chips for both sides -

8

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

Sensor N-side Contact Pads

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

N-side poly-Si resistors

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

N-side p-stops configuration

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

N-side Guard Rings

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

Sensor P-side 1st and 2nd metal

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

Sensor P-side 1st and 2nd metal details

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

P-side Guard Rings

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

Results

•Number of masks:•N-side – 8•P-side – 9

•Estimated production time - 3 months + 1 month for masks production.

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

Expected

• Full Depletion Voltage (FDV) - <50 V• Working voltage – 70 - 250 V• Dark current at 100 V – < 15 nА/см2

• AC capacitance - >10 pF/см• Capacitors breakdown voltage -

>170 V• Bias resistor value - 1.0 ± 0.4 MOhm• Number of bad strips - <0.5%/side

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia

Last

• This work have been done within CBM-MPD STS Consortium and supported by ISTC, see Yu. Murin presentation

1-st CBM-Russia-JINR Collaboration Meeting May 19-22, 2009, Dubna, Russia