1. Development of Silicon Microstrip Sensors in 150 mm p-type Wafers
Y. Unno, S.Terada, Y.Ikegami, T. Kohriki, K.Hara, and the ATLAS R&D collaboration of "Development of non-inverting Silicon strip detectors for the ATLAS ID upgrade"
K. Yamamura, S. Kamada (Hamamatsu Photonics)
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

2. Some History of Development
1995 p-type 4-inch (100 mm) wafer (p95)
FZ(111) (~6 kΩcm) wafers
2005 p-type 4-inch (100 mm) wafer (ATLAS05)
FZ(111) (~6k Ωcm)
MCZ(100) (~900 Ωcm) wafers
2006 p-type 6-inch (150 mm) wafer (ATLAS06)
FZ-1(100)(~6.7k Ωcm), FZ-2(100)(~6.2k Ωcm)
MCZ(100)(~2.3k Ωcm)
2007 p-type 6-inch (150 mm) wafer (ATLAS07)
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

3. p95 p-type Sensors A prototype n-in-p sensor was fabricated in 1995
6 cm x 3 cm x 300 um, 50 um pitch, common p-stop
no DC-field plate over p-stop
p-bulk, (111), ~6 kΩcm
Irradiated up to 1.1 x 1014 p/cm2 at 12 GeV PS at KEK
A report was made in NIM A383(96)159
Re-measurements after 10yrs (irrad. stored at 0 C)
I-V
C-V
CCE with laser
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

4. ATLAS05 p-type Sensors Investigation of isolation of n-strips
p-stop with/without p-spray
With/without field-plate
p-stop doping levels
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

5. ATLAS05 p-type Sensors p-type wafers Sensors
4-inch wafer for cost reason
MCZ:
~900 Ωcm
Orientation (100)
FZ:
~6k Ωcm
Orientation (111)
Sensors
Miniature: 1cm x 1cm
Large: ((~1cm x ~6cm) x6 zones)
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

6. ATLAS06 p-type Sensors 6 inch (150 mm) wafer
FZ-1 (100), FZ-2 (100), MCZ
Further R&D of isolation structures
No DC-field plate
Width of (common) p-stop
p-stop/p-spray doping variations
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

7. ATLAS06 p-type Sensors Many miniature (1cm x 1cm) sensors
One sensor per one "Zone"
Large (3cm x 6 cm) sensors with 2 striplets
Variation of Polysilicon bias resistor connections
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

8. ATLAS07 p-type Sensors 6-inch (150 mm) wafer
Maximum size sensor (~10 cm x ~10 cm) prototyping
R&D's
Candidate isolation structures
"Punch-thru Protection" structures
Wide/Narrow metal effect
Wide/Narrow pitch effect
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

9. ATLAS07 p-type Sensors Full size (9.75 cm x 9.75 cm) prototype sensors
4 segments: two "axial" and two "stereo" (inclined) strips
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

10. Proton Irradiation at CYRIC
KEK
70 MeV protons
Beamline 32
Beamline 31-2
Facility associated with Univ. Tohoku, Sendai, Japan
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

11. Proton irradiations at CYRIC
AVF Cyclotron at Tohoku University
Beam energy: 70 MeV
Beam intensity: 10nA ~ 800nA
Beam spot size: ~5 mm FWHM
~4 min. for 1x1015 at 800 nA
Irradiation history
Beamline 31-2
st and beamline study
ATLAS05 - up to 5x1015
ATLAS06 - up to 2x1015 ,
Beamline 32
ATLAS07 - up to 1x1015
Change of beamline
Machine time/user conflict in 31
Straight, simpler line in 32
Beamline 31-2
Beamline 32
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

12. Laser for FDV and CCE Full Depletion Voltages (FDV)
C-V method
Laser method
Charge Collection Efficiencies (CCE)
Reference
sensor
Pulsed laser (1064nm) focused to 4um x 4um
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

13. Full Depletion Voltages
ATLAS05
CCE CV
ATLAS06
CCE
Very different fluence development in 4 inch and 6 inch!!
All p-type
4 inch FZ (111), though
FZ and MCZ are similar in 6 inch!!
except below ~2x1014 , no advantage in MCZ
FDV~500V!!
at 1x1015
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

14. CCE ATLAS06 ATLAS05 Charge loss up to 1x1015 is small
not fully depleted
VB=1kV
Charge loss up to 1x1015 is small
2x1015 appreciably less
No obvious difference is FZ and MCZ
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

15. Microdischarge ATLAS06 Onset voltage (VMD)
>600 V in FZ
some trouble in MCZ
Zone5 exceptional
After irradiation (>1x1014)
>1000 V!!
Even Zone5 and MCZ
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

16. N-strip Isolations + p-spray
Showing Vbias voltages to achieve isolation
Isolation gets worse as fluence accumulates
Number of observations can be seen from the plots....
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

17. TCAD Simulations N-P gap was too narrow
Potential of 2nd p-stops makes effective p-stop width as wide up to 2nd p-stop
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008

18. Summary
n-in-p p-type microstrip sensors have been fabricated in p-FZ and p-MCZ wafers, for several years by now
Proton irradiations, 70 MeV, are being routinely carried out at CYRIC of Tohoku Univ.,
Fluence development of full depletion voltage (FDV) of 4-inch (100 mm) and 6-inch (150 mm) is very different
In 6-inch, FDV is ~500 V at 1x1015 neq/cm2
CCE is near full up to 1x1015 neq/cm2
Onset voltage of the microdischarge has been achieved to be >600 V in general
Number of isolation structures are being investigated and we are narrowing the candidates
A full size microstrip sensor has been prototyped and we have the first look in hand
Y.Unno, 3rd Workshop on Advanced Silicon Radiation Detectors, Barcelona, Spain, April. 2008