Crosstalk measurements on particle sensors with unbiased and segmented guard-rings

The CALICE collaboration is involved in the development of calorimeters for the new generation of particle physics detectors. Technical limits are reached when building technological prototypes. In particular the integration process of the silicon P-I-N diodes matrices do not allow to bias the guard-rings. This leads to a disturbing crosstalk between the guard-rings and the nearest pixels. An initial modeling work has shown that still unbiased but segmented guard-rings could lower the couplings between the guard-rings and the pixels by at least 20 dB. The very first measurements results made on real prototypes are presented here and confirm the expectations taken from the various models.