High resolution X-ray photon-counting detector with scintillator-deposited charge-coupled device

Abstract

We report on a new photon-counting detector possessing unprecedented spatial resolution and moderate spectral resolution for 0.1-100 keV X-rays. It consists of an X-ray charge-coupled device (CCD) and scintillator. The scintillator is directly coupled to the back surface of the X-ray CCD. Low-energy X-rays below 10 keV can be directly detected by the CCD. The majority of hard X-rays above 10 keV pass through the CCD but can be absorbed by the scintillator, generating visible lights there. Since CCDs have a moderate detection efficiency, they can be detected by the CCD. We coupled the needlelike CsI(Tl) on the front surface of the back-illuminated (BI) CCD. High detection efficiency for visible lights of the BI CCD enables to collect visible lights emitted from CsI(Tl) efficiently, leading to the moderate spectral resolution of 30% both at 22.1 and 59.5 keV. We also investigated the imaging capability of our device and found it to be (10/spl plusmn/3) /spl mu/m at 17.4 keV.