1. Diamond Measurements in Zeuthen
Diamond samples
Fraunhofer Institute (Freiburg) :
(12 x 12 mm)
300 and 200 um
Different surface treatments :
#1 – substrate side polished; 300 um
#2 – cut substrate; 200 um
#3 – growth side polished; 300 um
#4 – both sides polished; 300 um
Metallization:
10 nm Ti nm Au

2. Electric Parameters of Freiburg Diamonds
I(V) dependence
Usual I(V) curve:
Non-ohmic
curve:

3. Time dependence :

4. Reproducibility:
Conclusion: currents of most diamonds of Freiburg production constitute several picoampers at operating voltages, which completely satisfies LCAL needs.

5. Charge Collection Distance of Freiburg Diamonds
Qmeas. = Qcreated x ccd / L
&
Gate PA
discr
delay
ADC
Sr90
PM1
PM2
diamond
Scint.
Not irradiated samples
CCD = f(HV)
Both polarities

6. Spectra obtained – noise and Sr signal

7. CCD - before irradiation (1)

8. CCD - before irradiation
Sensor
R(Average)
ccd Up 500V
ccd Up 800V
ccd Down 500V
ccd Down 800V 11
4.60E+13 37 35 12
3.20E+14 27 30 43 13
8.88E+11 21 25 33
5.92E+14 17 24 22
7.39E+14 9
10 (700V) 23
3.93E+14 10 31
1.04E+11
33 (400V) 28 32
5.12E+13 50 57
4.63E+13 52 58 49 54 41
5.12E+11 48
45 (400 V) 42
4.35E+14
5.24E+13 60 65

9. CCD – a spectra

10. Results: Values of CCD before irradiation: (10 - 60) um
Surface treatment has an influence on CCD
Good resistance doesn’t mean high CCD