First tests with fully depleted pn-CCD's

The authors fabricated 280 μm thick fully depletable pn CCD's on high resistivity silicon (rho ≅ 2.5 kΩcm). Its operation is based on the semiconductor drift chamber principle proposed by Gatti and Rehak. They are designed as energy and position sensitive radiation detectors for (minimum) ionizing particles and X-ray imaging. Two dimensional semiconductor device modeling demonstrates the basic charge transfer mechanisms. Prototypes of the detectors have been tested in static and dynamic conditions. A preliminary charge transfer inefficiency was determined to 6 . 10/sup -3/. The charge loss during the transfer is discussed and as a consequence the authors developed an improved design for a second fabrication iteration which is now being produced