Novel High Resolution, Low Dose Flat Panel Mammography Detector Technology
Abstract
This project is to apply a thin coating of thallium bromide (TIBr) to the surface of readout CMOS integrated circuits incorporated into a slot-scan mammography system. Such an approach would reduce the cost of sensor fabrication and provide a near 50% increase in quantum efficiency compared with silicon PIN diode detectors hybridized with CMOS readouts. To realize the technology, an evaporator and a sputtering system needed for this project have been assembled, modified, and tested for detector fabrication. A stripping process to remove indium bumps from CMOS readout integrated circuits has been developed. Two thallium-bromide-coated nonfunctional sensor arrays were fabricated and studied by scanning electron microscopy (SEM). Our initial findings indicate that no chemical attack was observed at the interface between thallium bromide and substrate. We, however, may have the adhesion problem of thallium bromide to the substrate material. We have been making efforts to search for a buffer material deposited prior to the growth of thallium bromide to resolve the issue. We expect to deliver two thallium-bromide-coasted nonfunctional sensor arrays for the evaluation of their X-ray imaging properties in February, March, and April, respectively. A prototype system will then be fully characterized in May.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2000
- Accession Number
- ADB262637