An electron image projector has been designed and built which is currently exposing 4 in. wafers and has the capability of going to 5 in. Linewidth control of ±0.04 μm for 1 μm lines has been measured over the whole surface of 4 in. wafers. Machine alignment accuracy of ±0.03 μm has been achieved and nonrepeatable image distortion is shown to be less than 0.1 μm. Examples of resolution capability and step coverage are also shown.
Abstract--. This article focuses on the characterisation of three versions of a custom designed silicon photodetector using nuclear spectroscopy techniques. Room temperature gamma ray spectroscopy experiments have been performed using an LYSO excited by 137 Cs and 22 Na sources and read out by the new photodiodes. We have measured an energy resolution of 13.1% FWHM for the 511 keV gamma rays from a 22 Na source and 11.2% FWHM for the 662 keV gamma rays from a 137 Cs source. This is one of the best ever-reported energy resolutions for a lutetium based scintillator crystal read out by a silicon photodetector.I. INTRODUCTION urrent commercial PET scanners are general purpose devices which are designed to support a wide range of clinical applications. These generally require a scanner with reasonably large detector ring diameter (≥80 cm) and the ability to image the whole body in incremental steps. Recently, new applications of PET have emerged which place different demands on PET instrumentation, requiring high spatial resolution and sensitivity, in particular for imaging small volumes. Such applications include small animal imaging, breast cancer imaging and high resolution brain imaging. With these emerging applications, a large ring diameter is not only not required but also limits the performance that can be achieved when imaging small volumes.
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