Speaker
Mr
Shingo Mitsui
(Sokendai/KEK (JP))
Description
The silicon pixel and strip sensors are required to work up to
the fluences of $¥geq$1$¥times$10$^{16}$ n/cm2 and
$¥geq$1$¥times$10$^{15}$n/cm2, respectively, for the high luminosity
upgrade of the LHC (HL-LHC). This requires a high sensor bias voltage of
1000 V applicable to cope with the radiation damage in the silicon bulk.
For planar sensors, the distance to the edge and multiple guard rings
are important parameters to withstand such high voltage while a minimum
inactive space in the edge is also important. The protection of the
sensor, especially the AC coupling insulator, against an accident of
beam splash is also to be considered to operate the sensors in the high
luminosity machine. We evaluate this with a punch-through-protection
(PTP) structures.
We have fabricated test diodes using p-bulk with various edge distances
(slim-edge diodes), with single to triple guard structures(multi-guard
diodes), and with variousPTP structures. Thesesamples were irradiated
with 70 MeV protons to the fluences of 5$¥times$10$^{12}$ up to
1$¥times$10$^{16}$ n/cm2.Through this fundamental study we have
determined the required edge space, evaluated the relevance ofthe
multiple guard to suppress the microdischargeonset and the effectiveness
of the PTP structures.
Author
Mr
Shingo Mitsui
(Sokendai/KEK (JP))
