  Silicon pad sensors with novel functions of higher timing resolution (LGAD:
Low Gain Avalanche Detector) and higher position resolution (PSD: Position
Sensitive Detector) are studied for an application to Silicon-Tungsten
electromagnetic calorimeter for a detector of the International Linear Collider
(ILC). Prototype sensors are fabricated, equipped with dedicated ASICs
(Application-Specific Integrated Circuits) and tested with a positron beam as
well as a radioisotope. The first results of the measurements of timing
resolution with LGADs and position reconstruction with PSDs are reported.

Instrumentation and Detectors