Patent ID: 7233005
Filing Date: 2007-06-19
Classification: H01L

Abstract:
1. A digital, flat panel x-ray imager exhibiting low ghosting and rapid recovery time, comprising: a substrate having an upper surface; a selenium-based charge generator layer on the upper surface of the substrate responsive to x-rays to generate electrical charges; a non-insulating organic layer directly on, and in physical contact with, an upper surface of the selenium-based charge generator layer; a top electrode directly on, and in physical contact with, an upper surface of the non-insulating organic layer; a charge collection electrode between the substrate and the charge generator layer, said charge collection electrode being divided into a two-dimensional array of pixel electrodes; a read-out circuit, also between the substrate and the charge generator layer, said read-out circuit comprising respective signal storage capacitors coupled with said pixel electrodes and storing electrical charge collected thereby from the charge generating layer, and further comprising a thin-film transistor array of respective gating transistors coupled with said signal storage capacitors; wherein each of said gating transistors is selectively switched between an ON state in which it passes charge from the respective storage capacitors to an outside circuit and an OFF state in which it passes leakage current; and wherein the leakage current of each of said gating transistors rises at a relatively low rate with rise in potential at the respective capacitor below the range of 20–25 volts but rises at a significantly higher rate with rise in potential at the respective capacitor above said range.