Fabrication of CdTe strip detectors for imaging applications

Abstract

p–i–n CdTe strip detectors were fabricated in a new and simple technique for their probable applications in astrophysics and medical imaging. The detector has an iodine-doped n-CdTe epitaxial layer followed by aluminum metallization on the Te-face of (1 1 1) oriented CdTe crystal, as an anode. The cathode consists of the p-type segmented regions formed on the crystal by the diffusion of dopant atoms from an alkaline metal compound through a patterned shadow mask using the excimer laser radiation. Afterward, the gold electrode is evaporated through the same shadow mask to make the strip cathodes. In a different way, we also studied the laser ablation process for the selective area etching by irradiating the laser through a mask. Details of these fabrication processes for making strip detectors and results on laser-assisted etching process will be presented.