First X-ray images with a double-sided microstrips silicon crystal. A novel detector for digital radiography?

Abstract

In the framework of an experimental program to study the possibility of using a silicon crystal for X-ray detection in the diagnostic energy range (10-100 keV), the authors present the first experimental results obtained with a silicon detector (300 mu m thick, 1.4*1.4 cm2 surface) with microstrips deposited on each side: 25 mu m spacing on the junction side and 50 mu m spacing on the ohmic side: 25 mu m spacing on the junction side and 50 mu m spacing on the ohmic side; the read-out pitch is 100 mu m for both sides. Energy and spatial resolutions have been measured by means of collimated radioactive sources: 241Am (E gamma =60 keV) and 109Cd (E gamma =24 and 88 keV). A very good linearity in the response to the photon energy has been measured. Tantalum wires, i.e. high contrast objects, have been used as phantoms when exposing the detector to the 60 keV photons; the authors present the images thus obtained.