Surface pattern of a Si Mini-Pad sensor for the PHENIX MPC-EX and damage caused by ionizing radiation

Abstract

The Si Mini-Pad sensor is an essential component of the MPC-EX preshower detector. This detector will be integrated into the PHENIX experiment at Brookhaven National Laboratory's Relativistic Heavy Ion Collider. We describe the development of the surface pattern and the fabrication process of the Si Mini-Pad sensor and present a test by the low energy gamma irradiation that is sensitive to the surface design.