A NOVEL CATHODE STRUCTURE FOR A SELF-BIASED LINEAR SILICON-DRIFT-DETECTOR

A novel cathode structure for a self-biased linear Silicon Drift Detec tor (SDD) is presented. The proper potential profile inside the fully depleted substrate is established by the voltage drop along a single c athode implanted across each external surface and arranged as a zigzag . Compared to other self-biased linear SDDs, the proposed structure fe atures a uniform thermal distribution and optimizes the sensitive area . The Poisson's equation together with the proper boundary conditions has been analytically solved in the 3D domain, and the solution has be en validated by means of 3D simulation. A prototype based on this geom etrical configuration has been manufactured at Canberra Semiconductor. The resistance spread of each portion which constitutes the implanted cathode has been measured and results within 2%.