Characteristics of a PDP-Based Radiation Detector Dependent on Different Electrode Structures

Abstract

In this study, a flat-panel detector based on plasma display technology was investigated as a candidate for a flat-panel radiation detector. We studied the dependence of multiplication factors on various electrode structures using the 3-D Garfield code that calculates the passage of particles through the gas-filled gap. Prototype detectors having three different electrode structures were designed and fabricated based on the simulation results. The performances of these detectors were examined by measuring the collected charge density, dark current density, and sensitivity. The collected charge density had the highest value at the condition when the ridged electrode structure was 1.57 $\mu \text{C}$ /cm2 at −1500 V. The dark current of the same detector was varied between 4.8 and 6.17 nA/cm2 at the bias range of −500 to −1500 V. The sensitivity of the ridged electrode detector was 0.363 nC/ ${\rm mR}\,\cdot \,{\rm cm}^{2}$ at 0.54 V/ $\mu \text{m}$ , and it is approaching to 18% of the sensitivity reported for the commercially available amorphous selenium (a-Se) detector at 10 V/ $\mu \text{m}$ .